ack-flood detect { ip ipv4-address | ipv6 ipv6-address } [ vpn-instance vpn-instance-name ] [ threshold threshold-value ] [ action { { drop | logging } * | none } ]

undo ack-flood detect { ip ipv4-address | ipv6 ipv6-address } [ vpn-instance vpn-instance-name ]

Default

IP address-specific ACK flood attack detection is not configured.

Views

Attack defense policy view

Predefined user roles

network-admin

mdc-admin

Parameters

ip ipv4-address: Specifies the IPv4 address to be protected. The ip-address argument cannot be all 1s or 0s.

ipv6 ipv6-address: Specifies the IPv6 address to be protected.

vpn-instance vpn-instance-name: Specifies the MPLS L3VPN instance to which the protected IP address belongs. The vpn-instance-name argument is a case-sensitive string of 1 to 31 characters. Do not specify this option if the protected IP address is on the public network.

threshold threshold-value: Specifies the threshold for triggering ACK flood attack prevention. The value range is 1 to 1000000 in units of ACK packets sent to the specified IP address per second.

action: Specifies the actions when an ACK flood attack is detected. If no action is specified, the global actions set by the ack-flood action command apply.

drop: Drops subsequent ACK packets destined for the protected IP address.

logging: Enables logging for ACK flood attack events.

none: Takes no action.

Usage guidelines

With ACK flood attack detection configured for an IP address, the device is in attack detection state. When the sending rate of ACK packets to the IP address reaches the threshold, the device enters prevention state and takes the specified actions. When the rate is below the silence threshold (three-fourths of the threshold), the device returns to the attack detection state.

You can configure ACK flood attack detection for multiple IP addresses in one attack defense policy.

Examples

# Configure ACK flood attack detection for 192.168.1.2 in attack defense policy atk-policy-1.

<Sysname> system-view

[Sysname] attack-defense policy atk-policy-1

[Sysname-attack-defense-policy-atk-policy-1] ack-flood detect ip 192.168.1.2 threshold 2000

Related commands

ack-flood action

ack-flood detect non-specific

ack-flood threshold

ack-flood detect non-specific

Use ack-flood detect non-specific to enable global ACK flood attack detection.

Use undo ack-flood detect non-specific to disable global ACK flood attack detection.

Syntax

ack-flood detect non-specific

undo ack-flood detect non-specific

Default

Global ACK flood attack detection is disabled.

Views

Attack defense policy view

Predefined user roles

network-admin

mdc-admin

Usage guidelines

The global ACK flood attack detection applies to all IP addresses except those specified by the ack-flood detect command. The global detection uses the global trigger threshold set by the ack-flood threshold command and global actions specified by the ack-flood action command.

Examples

# Enable global ACK flood attack detection in attack defense policy atk-policy-1.

<Sysname> system-view

[Sysname] attack-defense policy atk-policy-1

[Sysname-attack-defense-policy-atk-policy-1] ack-flood detect non-specific

Related commands

ack-flood action

ack-flood detect

ack-flood threshold

Use ack-flood threshold to set the global threshold for triggering ACK flood attack prevention.

Use undo ack-flood threshold to restore the default.

Syntax

ack-flood threshold threshold-value

undo ack-flood threshold

Default

The global threshold is 1000 for triggering ACK flood attack prevention.

Views

Attack defense policy view

Predefined user roles

network-admin

mdc-admin

Parameters

threshold-value: Specifies the threshold value. The value range is 1 to 1000000 in units of ACK packets sent to an IP address per second.

Usage guidelines

With global ACK flood attack detection configured, the device is in attack detection state. When the sending rate of ACK packets to an IP address reaches the threshold, the device enters prevention state and takes the specified actions. When the rate is below the silence threshold (three-fourths of the threshold), the device returns to the attack detection state.

The global threshold applies to global ACK flood attack detection. Adjust the threshold according to the application scenarios. If the number of ACK packets sent to a protected server, such as an HTTP or FTP server, is normally large, set a large threshold. A small threshold might affect the server services. For a network that is unstable or susceptible to attacks, set a small threshold.

Examples

# Set the global threshold to 100 for triggering ACK flood attack prevention in attack defense policy atk-policy-1.

<Sysname> system-view

[Sysname] attack-defense policy atk-policy-1

[Sysname-attack-defense-policy-atk-policy-1] ack-flood threshold 100

Related commands

ack-flood action

ack-flood detect

ack-flood detect non-specific

attack-defense local apply policy

Use attack-defense local apply policy to apply an attack defense policy to the device.

Use undo attack-defense local apply policy to restore the default.

Syntax

attack-defense local apply policy policy-name

undo attack-defense local apply policy

Default

No attack defense policy is applied to the device.

Views

System view

Predefined user roles

network-admin

mdc-admin

Parameters

Usage guidelines

An attack defense policy applied to the device itself detects packets destined for the device and prevents attacks targeted at the device.

A switch uses hardware to implement packet forwarding and uses software to process packets if the packets are destined for the switch. The software does not provide any attack defense features, so you must apply an attack defense policy to the switch to prevent attacks aimed at the switch.

Each device can have only one attack defense policy applied. If you execute this command multiple times, the most recent configuration takes effect.

Examples

# Apply attack defense policy atk-policy-1 to the device.

<Sysname> system-view

[Sysname] attack-defense local apply policy atk-policy-1

Related commands

attack-defense policy

display attack-defense policy

attack-defense login reauthentication-delay

Use attack-defense login reauthentication-delay to enable the login delay feature.

Use undo attack-defense login reauthentication-delay to restore the default.

Syntax

attack-defense login reauthentication-delay seconds

undo attack-defense login reauthentication-delay

Default

The login delay feature is disabled. The device does not delay accepting a login request from a user who has failed a login attempt.

Views

System view

Predefined user roles

network-admin

mdc-admin

Parameters

seconds: Specifies the delay period in seconds, in the range of 4 to 60.

Usage guidelines

The login delay feature delays the device to accept a login request from a user after the user fails a login attempt. This feature can slow down login dictionary attacks.

The login delay feature is independent of the login attack prevention feature.

Examples

# Enable the login delay feature and set the delay period to 5 seconds.

<Sysname> system-view

[Sysname] attack-defense login reauthentication-delay 5

attack-defense policy

Use attack-defense policy to create an attack defense policy and enter its view, or enter the view of an existing attack defense policy.

Use undo attack-defense policy to delete an attack defense policy.

Syntax

attack-defense policy policy-name

undo attack-defense policy policy-name

Default

No attack defense policies exist.

Views

System view

Predefined user roles

network-admin

mdc-admin

Parameters

policy-name: Assigns a name to the attack defense policy. The policy name is a case-insensitive string of 1 to 31 characters. Valid characters include uppercase and lowercase letters, digits, underscores (_), and hyphens (-).

Usage guidelines

CAUTION:

The default thresholds for triggering attack prevention might not be appropriate for your network. Set appropriate thresholds according to the actual application scenarios. Small thresholds might affect the Internet or webpage access speed. Large thresholds might make your network vulnerable to attacks.

‌

Examples

# Create attack defense policy atk-policy-1 and enter its view.

<Sysname> system-view

[Sysname] attack-defense policy atk-policy-1

[Sysname-attack-defense-policy-atk-policy-1]

Related commands

attack-defense apply policy

display attack-defense policy

attack-defense signature log non-aggregate

Use attack-defense signature log non-aggregate to enable log non-aggregation for single-packet attack events.

Use undo attack-defense signature log non-aggregate to restore the default.

Syntax

attack-defense signature log non-aggregate

undo attack-defense signature log non-aggregate

Default

Log non-aggregation is disabled for single-packet attack events.

Views

System view

Predefined user roles

network-admin

mdc-admin

Usage guidelines

Log aggregation aggregates multiple logs generated during a period of time and sends one log. Logs that are aggregated must have the following attributes in common:

· Location where the attacks are detected: device.

· Attack type.

· Attack prevention action.

· Source and destination IP addresses.

· VPN instance to which the victim IP address belongs.

As a best practice, do not disable log aggregation. A large number of logs will consume the display resources of the console.

Examples

# Enable log non-aggregation for single-packet attack events.

<Sysname> system-view

[Sysname] attack-defense signature log non-aggregate

Related commands

signature detect

attack-defense tcp fragment enable

Use attack-defense tcp fragment enable to enable TCP fragment attack prevention.

Use undo attack-defense tcp fragment enable to disable TCP fragment attack prevention.

Syntax

attack-defense tcp fragment enable

undo attack-defense tcp fragment enable

Default

TCP fragment attack prevention is enabled.

Views

System view

Predefined user roles

network-admin

mdc-admin

Usage guidelines

This command enables the device to drop attack TCP fragments to prevent TCP fragment attacks that the packet filter cannot detect. As defined in RFC 1858, attack TCP fragments refer to the following TCP fragments:

· First fragments in which the TCP header is smaller than 20 bytes.

· Non-first fragments with a fragment offset of 8 bytes (FO=1).

TCP fragment attack prevention takes precedence over single-packet attack prevention. When both are used, incoming TCP packets are processed first by TCP fragment attack prevention and then by the single-packet attack defense policy.

Examples

# Enable TCP fragment attack prevention.

<Sysname> System-view

[Sysname] attack-defense tcp fragment enable

display attack-defense flood statistics ip

Use display attack-defense flood statistics ip to display IPv4 flood attack detection and prevention statistics.

Syntax

In standalone mode:

display attack-defense { ack-flood | dns-flood | fin-flood | flood | http-flood | icmp-flood | rst-flood | syn-ack-flood | syn-flood | udp-flood } statistics ip [ ip-address [ vpn vpn-instance-name ] ] [ [ local ] [ slot slot-number ] ] [ count ]

In IRF mode:

Views

Any view

Predefined user roles

network-admin

network-operator

mdc-admin

mdc-operator

Parameters

ack-flood: Specifies ACK flood attack.

dns-flood: Specifies DNS flood attack.

fin-flood: Specifies FIN flood attack.

flood: Specifies all IPv4 flood attacks.

http-flood: Specifies HTTP flood attack.

icmp-flood: Specifies ICMP flood attack.

rst-flood: Specifies RST flood attack.

syn-ack-flood: Specifies SYN-ACK flood attack.

syn-flood: Specifies SYN flood attack.

udp-flood: Specifies UDP flood attack.

ip-address: Specifies a protected IPv4 address. If you do not specify an IPv4 address, this command displays flood attack detection and prevention statistics for all protected IPv4 addresses.

vpn-instance vpn-instance-name: Specifies the MPLS L3VPN instance to which the protected IPv4 address belongs. The vpn-instance-name argument is a case-sensitive string of 1 to 31 characters. Do not specify this option if the protected IPv4 address is on the public network.

local: Specifies the device.

slot slot-number: Specifies a card by its slot number. This option is available only when you specify the device. If you do not specify a card, this command displays IPv4 flood attack detection and prevention statistics for all cards. (In standalone mode.)

chassis chassis-number slot slot-number: Specifies a card on an IRF member device. The chassis-number argument represents the member ID of the IRF member device. The slot-number argument represents the slot number of the card. This option is available only when you specify the device. If you do not specify a card, this command displays IPv4 flood attack detection and prevention statistics for all cards. (In IRF mode.)

Usage guidelines

The device collects statistics about protected IP addresses for flood attack detection and prevention. The attackers' IP addresses are not recorded.

Examples

# (In standalone mode.) Display all IPv4 flood attack detection and prevention statistics.

<Sysname> display attack-defense flood statistics ip

slot 1:

IP address VPN Detected on Detect type State PPS Dropped

201.55.7.44 -- Local DNS-FLOOD Normal 1000 111111111

192.168.11.4 -- Local ACK-FLOOD Normal 1000 22222222

slot 2:

IP address VPN Detected on Detect type State PPS Dropped

192.168.100.66 -- Local SYN-ACK-FLOOD Normal 1000 165467998

# (In standalone mode.) Display the number of IPv4 addresses that are protected against flood attacks.

<Sysname> display attack-defense flood statistics ip count

Slot 1:

Totally 2 flood entries.

Slot 2:

Totally 1 flood entries.

Table 1 Command output

Field	Description
IP address	Protected IPv4 address.
VPN	MPLS L3VPN instance to which the protected IPv4 address belongs. If the protected IPv4 address is on the public network, this field displays hyphens (--).
Detected on	Where the attack is detected: the device (Local).
Detect type	Type of the detected flood attack.
State	Whether the device is attacked: · Attacked. · Normal.
PPS	Number of packets sent to the IPv4 address per second.
Dropped	Number of attack packets dropped by the device.
Totally 2 flood entries	Total number of IPv4 addresses that are protected.

display attack-defense flood statistics ipv6

Use display attack-defense flood statistics ipv6 to display IPv6 flood attack detection and prevention statistics.

Syntax

In standalone mode:

display attack-defense { ack-flood | dns-flood | fin-flood | flood | http-flood | icmpv6-flood | rst-flood | syn-flood | syn-ack-flood | udp-flood } statistics ipv6 [ ipv6-address [ vpn vpn-instance-name ] ] [ [ local ] [ slot slot-number ] ] [ count ]

In IRF mode:

Views

Any view

Predefined user roles

network-admin

network-operator

mdc-admin

mdc-operator

Parameters

ack-flood: Specifies ACK flood attack.

dns-flood: Specifies DNS flood attack.

fin-flood: Specifies FIN flood attack.

flood: Specifies all IPv6 flood attacks.

http-flood: Specifies HTTP flood attack.

icmpv6-flood: Specifies ICMPv6 flood attack.

rst-flood: Specifies RST flood attack.

syn-ack-flood: Specifies SYN-ACK flood attack.

syn-flood: Specifies SYN flood attack.

udp-flood: Specifies UDP flood attack.

ipv6-address: Specifies a protected IPv6 address. If you do not specify an IPv6 address, this command displays flood attack detection and prevention statistics for all protected IPv6 addresses.

vpn-instance vpn-instance-name: Specifies the MPLS L3VPN instance to which the protected IPv6 address belongs. The vpn-instance-name argument is a case-sensitive string of 1 to 31 characters. Do not specify this option if the protected IPv6 address is on the public network.

local: Specifies the device.

slot slot-number: Specifies a card by its slot number. This option is available only when you specify the device. If you do not specify a card, this command displays IPv6 flood attack detection and prevention statistics for all cards. (In standalone mode.)

chassis chassis-number slot slot-number: Specifies a card on an IRF member device. The chassis-number argument represents the member ID of the IRF member device. The slot-number argument represents the slot number of the card. This option is available only when you specify the device. If you do not specify a card, this command displays IPv6 flood attack detection and prevention statistics for all cards. (In IRF mode.)

Usage guidelines

The device collects statistics about protected IP addresses for flood attack detection and prevention. The attackers' IP addresses are not recorded.

Examples

# (In standalone mode.) Display all IPv6 flood attack detection and prevention statistics.

<Sysname> display attack-defense flood statistics ipv6

Slot 1:

IPv6 address VPN Detected on Detect type State PPS Dropped

1::4 -- Local ACK-FLOOD Normal 1000 111111111

1::5 -- Local SYN-FLOOD Normal 1000 22222222

Slot 2:

IPv6 address VPN Detected on Detect type State PPS Dropped

1::6 -- Local DNS-FLOOD Normal 1000 12569985

# (In standalone mode.) Display the number of IPv6 addresses that are protected against flood attacks.

<Sysname> display attack-defense flood statistics ipv6 count

Slot 1:

Totally 2 flood entries.

Slot 2:

Totally 1 flood entries.

Table 2 Command output

Field	Description
IPv6 address	Protected IPv6 address.
VPN	MPLS L3VPN instance to which the protected IPv6 address belongs. If the protected IPv6 address is on the public network, this field displays hyphens (--).
Detected on	Where the attack is detected: the device (Local).
Detect type	Type of the detected flood attack.
State	Whether the device is attacked: · Attacked. · Normal.
PPS	Number of packets sent to the IPv6 address per second.
Dropped	Number of attack packets dropped by the device.
Totally 2 flood entries	Total number of IPv6 addresses that are protected.

display attack-defense policy

Use display attack-defense policy to display attack defense policy configuration.

Syntax

display attack-defense policy [ policy-name ]

Views

Any view

Predefined user roles

network-admin

network-operator

mdc-admin

mdc-operator

Parameters

policy-name: Specifies an attack defense policy by its name. The policy name is a case-insensitive string of 1 to 31 characters. Valid characters include uppercase and lowercase letters, digits, underscores (_), and hyphens (-). If no attack defense policy is specified, this command displays brief information about all attack defense policies.

Usage guidelines

This command output includes the following configuration information about an attack defense policy:

· Whether attack detection is enabled.

· Attack prevention actions.

· Attack prevention trigger thresholds.

Examples

# Display the configuration of attack defense policy abc.

<Sysname> display attack-defense policy abc

Attack-defense Policy Information

--------------------------------------------------------------------------

Policy name : abc

Applied list : Local

--------------------------------------------------------------------------

Exempt IPv4 ACL: : Not configured

Exempt IPv6 ACL: : vip

--------------------------------------------------------------------------

Actions: CV-Client verify BS-Block source L-Logging D-Drop N-None

Signature attack defense configuration:

Signature name Defense Level Actions

Fragment Enabled Info L

Impossible Enabled Info L

Teardrop Disabled Info L

Tiny fragment Disabled Info L

IP option abnormal Disabled Info L

Smurf Disabled Info N

Traceroute Disabled Medium L,D

Ping of death Disabled Low L

Large ICMP Disabled Medium L,D

Max length 4000 bytes

Large ICMPv6 Disabled Low L

Max length 4000 bytes

TCP invalid flags Disabled medium L,D

TCP null flag Disabled Low L

TCP all flags Enabled Info L

TCP SYN-FIN flags Disabled Info L

TCP FIN only flag Enabled Info L

TCP Land Disabled Info L

Winnuke Disabled Info L

UDP Bomb Disabled Info L

UDP Snork Disabled Info L

UDP Fraggle Enabled Info L

IP option record route Disabled Info L

IP option internet timestamp Enabled Info L

IP option security Disabled Info L

IP option loose source routing Enabled Info L

IP option stream ID Disabled Info L

IP option strict source routing Disabled Info L

IP option route alert Disabled Info L

ICMP echo request Disabled Info L

ICMP echo reply Disabled Info L

ICMP source quench Disabled Info L

ICMP destination unreachable Enabled Info L

ICMP redirect Enabled Info L

ICMP time exceeded Enabled Info L

ICMP parameter problem Disabled Info L

ICMP timestamp request Disabled Info L

ICMP timestamp reply Disabled Info L

ICMP information request Disabled Info L

ICMP information reply Disabled Medium L,D

ICMP address mask request Disabled Medium L,D

ICMP address mask reply Disabled Medium L,D

ICMPv6 echo request Enabled Medium L,D

ICMPv6 echo reply Disabled Medium L,D

ICMPv6 group membership query Disabled Medium L,D

ICMPv6 group membership report Disabled Medium L,D

ICMPv6 group membership reduction Disabled Medium L,D

ICMPv6 destination unreachable Enabled Medium L,D

ICMPv6 time exceeded Enabled Medium L,D

ICMPv6 parameter problem Disabled Medium L,D

ICMPv6 packet too big Disabled Medium L,D

Scan attack defense configuration:

Defense: Disabled

Level: Medium

Actions: L

Flood attack defense configuration:

Flood type Global thres(pps) Global actions Service ports Non-specific

SYN flood 1000(default) - - Disabled

ACK flood 1000(default) - - Enabled

SYN-ACK flood 1000(default) - - Disabled

RST flood 200 - - Enabled

FIN flood 1000(default) L,D - Disabled

UDP flood 1000(default) - - Disabled

ICMP flood 1000(default) - - Disabled

ICMPv6 flood 1000(default) CV - Disabled

DNS flood 10000 - 30,61 to 62 Enabled

HTTP flood 10000 - 80,8080 Enabled

Flood attack defense for protected IP addresses:

Address VPN instance Flood type Thres(pps) Actions Ports

1::1 -- FIN-FLOOD 10 L,D -

192.168.1.1 -- SYN-ACK-FLOOD 10 - -

1::1 -- FIN-FLOOD - L -

2013:2013:2013:2013: -- DNS-FLOOD 100 L,CV 53

2013:2013:2013:2013

Table 3 Command output

Field	Description
Policy name	Name of the attack defense policy.
Applied list	Locations to which the attack defense policy is applied: Local (Local indicates that the policy is applied to the device).
Exempt IPv4 ACL	IPv4 ACL used for attack detection exemption.
Exempt IPv6 ACL	IPv6 ACL used for attack detection exemption.
Actions	Attack prevention actions: · CV—Client verification. · BS—Blocking sources. · L—Logging. · D—Dropping packets. · N—No action.
Signature attack defense configuration	Configuration information about single-packet attack detection and prevention.
Signature name	Type of the single-packet attack.
Defense	Whether attack detection is enabled.
Level	Level of the single-packet attack, info, low, medium, or high. Currently, no high-level single-packet attacks exist.
Large ICMPv6	Large ICMPv6 attack.
ICMPv6 echo request	ICMPv6 echo request attack.
ICMPv6 echo reply	ICMPv6 echo reply attack.
ICMPv6 group membership query	ICMPv6 group membership query attack.
ICMPv6 group membership report	ICMPv6 group membership report attack.
ICMPv6 group membership reduction	ICMPv6 group membership reduction attack.
ICMPv6 destination unreachable	ICMPv6 destination unreachable attack.
ICMPv6 time exceeded	ICMPv6 time exceeded attack.
ICMPv6 parameter problem	ICMPv6 parameter problem attack.
ICMPv6 packet too big	ICMPv6 packet too big attack.
Scan attack defense configuration	Configuration information about scanning attack detection and prevention.
Level	Level of the scanning attack detection: low, medium, or high.
Flood attack defense configuration	Configuration information about flood attack detection and prevention.
Flood type	Type of the flood attack: · ACK flood. · DNS flood. · FIN flood. · ICMP flood. · ICMPv6 flood. · SYN flood. · SYN-ACK flood. · UDP flood. · RST flood. · HTTP flood.
Global thres (pps)	Global threshold for triggering the flood attack prevention, in units of packets sent to an IP address per second. The default is 1000 pps.
Global actions	Global prevention actions against the flood attack: · D—Dropping packets. · L—Logging. · CV—Client verification. · -—Not configured.
Service ports	Ports that are protected against the flood attack. This field displays port numbers only for the DNS and HTTP flood attacks. For other flood attacks, this field displays a hyphen (-).
Non-specific	Whether the global flood attack detection is enabled.
Flood attack defense for protected IP addresses	Configuration of the IP address-specific flood attack detection and prevention.
Address	Protected IP address.
VPN instance	MPLS L3VPN instance to which the protected IP address belongs. If no MPLS L3VPN instance is specified, this field displays a hyphen (-).
Thres(pps)	Threshold for triggering the flood attack prevention, in units of packets sent to the IP address per second. If no threshold is specified, this field displays a hyphen (-).
Ports	Ports that are protected against the flood attack. This field displays port numbers only for the DNS and HTTP flood attacks. For other flood attacks, this field displays a hyphen (-).

# Display brief information about all attack defense policies.

<Sysname> display attack-defense policy

Attack-defense Policy Brief Information

------------------------------------------------------------

Policy Name Applied list

P2 None

p1 Local

p12 Local

Table 4 Command output

Field	Description
Policy name	Name of the attack defense policy.
Applied list	Locations to which the attack defense policy is applied: Local (Local indicates that the policy is applied to the device).

Related commands

attack-defense policy

display attack-defense policy ip

Use display attack-defense policy ip to display information about IPv4 addresses protected by flood attack detection and prevention.

Syntax

In standalone mode:

display attack-defense policy policy-name { ack-flood | dns-flood | fin-flood | flood | http-flood | icmp-flood | rst-flood | syn-ack-flood | syn-flood | udp-flood } ip [ ip-address [ vpn vpn-instance-name ] ] [ slot slot-number ] [ count ]

In IRF mode:

Views

Any view

Predefined user roles

network-admin

network-operator

mdc-admin

mdc-operator

Parameters

ack-flood: Specifies ACK flood attack.

dns-flood: Specifies DNS flood attack.

fin-flood: Specifies FIN flood attack.

flood: Specifies all IPv4 flood attacks.

http-flood: Specifies HTTP flood attack.

icmp-flood: Specifies ICMP flood attack.

rst-flood: Specifies RST flood attack.

syn-ack-flood: Specifies SYN-ACK flood attack.

syn-flood: Specifies SYN flood attack.

udp-flood: Specifies UDP flood attack.

ip-address: Specifies a protected IPv4 address. If you do not specify an IPv4 address, this command displays information about all protected IPv4 addresses.

vpn-instance vpn-instance-name: Specifies the MPLS L3VPN instance to which the IPv4 address belongs. The vpn-instance-name argument is a case-sensitive string of 1 to 31 characters. Do not specify this option if the IPv4 address is on the public network.

slot slot-number: Specifies a card by its slot number. If you do not specify a card, this command displays information about IPv4 addresses protected by flood attack detection and prevention for all cards. (In standalone mode.)

chassis chassis-number slot slot-number: Specifies a card on an IRF member device. The chassis-number argument represents the member ID of the IRF member device. The slot-number argument represents the slot number of the card. If you do not specify a card, this command displays information about IPv4 addresses protected by flood attack detection and prevention for all cards. (In IRF mode.)

count: Displays the number of matching IPv4 addresses protected by flood attack detection and prevention.

Examples

# (In standalone mode.) Display information about all IPv4 addresses protected by flood attack detection and prevention in attack defense policy abc.

<Sysname> display attack-defense policy abc flood ip

Slot 1:

IP address VPN instance Type Rate threshold(PPS) Dropped

123.123.123.123 -- SYN-ACK-FLOOD 100 4294967295

201.55.7.45 -- ICMP-FLOOD 100 10

192.168.11.5 -- DNS-FLOOD 23 100

Slot 2:

IP address VPN instance Type Rate threshold(PPS) Dropped

# (In standalone mode.) Display the number of IPv4 addresses protected by flood attack detection and prevention in attack defense policy abc.

<Sysname> display attack-defense policy abc flood ip count

Slot 1:

Totally 3 flood protected IP addresses.

Slot 2:

Totally 0 flood protected IP addresses.

Table 5 Command output

Field	Description
Totally 3 flood protected IP addresses	Total number of the IPv4 addresses protected by flood attack detection and prevention.
IP address	Protected IPv4 address.
VPN instance	MPLS L3VPN instance to which the protected IPv4 address belongs. If the protected IPv4 address is on the public network, this field displays hyphens (--).
Type	Type of the flood attack.
Rate threshold(PPS)	Threshold for triggering the flood attack prevention, in units of packets sent to the IP address per second. If no rate threshold is set, this field displays a hyphen (-).
Dropped	Number of dropped attack packets. If the prevention action is logging, this field displays 0.

display attack-defense policy ipv6

Use display attack-defense policy ipv6 to display information about IPv6 addresses protected by flood attack detection and prevention.

Syntax

In standalone mode:

display attack-defense policy policy-name { ack-flood | dns-flood | fin-flood | flood | http-flood | icmpv6-flood | rst-flood | syn-ack-flood | syn-flood | udp-flood } ipv6 [ ipv6-address [ vpn vpn-instance-name ] ] [ slot slot-number ] ] [ count ]

In IRF mode:

Views

Any view

Predefined user roles

network-admin

network-operator

mdc-admin

mdc-operator

Parameters

ack-flood: Specifies ACK flood attack.

dns-flood: Specifies DNS flood attack.

fin-flood: Specifies FIN flood attack.

flood: Specifies all IPv6 flood attacks.

http-flood: Specifies HTTP flood attack.

icmpv6-flood: Specifies ICMPv6 flood attack.

rst-flood: Specifies RST flood attack.

syn-ack-flood: Specifies SYN-ACK flood attack.

syn-flood: Specifies SYN flood attack.

udp-flood: Specifies UDP flood attack.

ipv6-address: Specifies a protected IPv6 address. If you do not specify an IPv6 address, this command displays information about all protected IPv6 addresses.

vpn-instance vpn-instance-name: Specifies the MPLS L3VPN instance to which the IPv6 address belongs. The vpn-instance-name argument is a case-sensitive string of 1 to 31 characters. Do not specify this option if the IPv6 address is on the public network.

slot slot-number: Specifies a card by its slot number. If you do not specify a card, this command displays information about IPv6 addresses protected by flood attack detection and prevention for all cards. (In standalone mode.)

chassis chassis-number slot slot-number: Specifies a card on an IRF member device. The chassis-number argument represents the member ID of the IRF member device. The slot-number argument represents the slot number of the card. If you do not specify a card, this command displays information about IPv6 addresses protected by flood attack detection and prevention for all cards. (In IRF mode.)

count: Displays the number of matching IPv6 addresses protected by flood attack detection and prevention.

Examples

# (In standalone mode.) Display information about all IPv6 addresses protected by flood attack detection and prevention in attack defense policy abc.

<Sysname> display attack-defense policy abc flood ipv6

Slot 1:

IPv6 address VPN instance Type Rate threshold(PPS) Dropped

2013::127f -- SYN-ACK-FLOOD 100 4294967295

2::5 -- ACK-FLOOD 100 10

1::5 -- ACK-FLOOD 100 23

Slot 2:

IPv6 address VPN instance Type Rate threshold(PPS) Dropped

# (In standalone mode.) Display the number of IPv6 addresses protected by flood attack detection and prevention in attack defense policy abc.

<Sysname> display attack-defense policy abc flood ipv6 count

Slot 1:

Totally 3 flood protected IP addresses.

Slot 2:

Totally 0 flood protected IP addresses.

Table 6 Command output

Field	Description
Totally 3 flood protected IP addresses	Total number of the IPv6 addresses protected by flood attack detection and prevention.
IPv6 address	Protected IPv6 address.
VPN instance	MPLS L3VPN instance to which the protected IPv6 address belongs. If the protected IPv6 address is on the public network, this field displays hyphens (--).
Type	Type of the flood attack.
Rate threshold(PPS)	Threshold for triggering the flood attack prevention, in units of packets sent to the IPv6 address per second. If no rate threshold is set, this field displays a hyphen (-).
Dropped	Number of dropped attack packets. If the prevention action is logging, this field displays 0.

display attack-defense scan attacker ip

Use display attack-defense scan attacker ip to display information about IPv4 scanning attackers.

Syntax

In standalone mode:

display attack-defense scan attacker ip [ [ local ] [ slot slot-number ] ] [ count ]

In IRF mode:

display attack-defense scan attacker ip [ [ local ] [ chassis chassis-number slot slot-number ] ] [ count ]

Views

Any view

Predefined user roles

network-admin

network-operator

mdc-admin

mdc-operator

Parameters

local: Specifies the device.

slot slot-number: Specifies a card by its slot number. This option is available only when you specify the device. If you do not specify a card, this command displays information about IPv4 scanning attackers for all cards. (In standalone mode.)

chassis chassis-number slot slot-number: Specifies a card on an IRF member device. The chassis-number argument represents the member ID of the IRF member device. The slot-number argument represents the slot number of the card. This option is available only when you specify the device. If you do not specify a card, this command displays information about IPv4 scanning attackers for all cards. (In IRF mode.)

Usage guidelines

If you do not specify any parameters, this command displays information about all IPv4 scanning attackers.

Examples

# (In standalone mode.) Display information about all IPv4 scanning attackers.

<Sysname> display attack-defense scan attacker ip

Slot 1:

IP address VPN instance DS-Lite tunnel peer Detected on Duration(min)

192.68.11.2 -- -- Local 782

Slot 2:

IP address VPN instance DS-Lite tunnel peer Detected on Duration(min)

# (In standalone mode.) Display the number of IPv4 scanning attackers.

<Sysname> display attack-defense scan attacker ip count

Slot 1:

Totally 1 attackers.

Slot 2:

Totally 0 attackers.

Table 7 Command output

Field	Description
Totally 1 attackers	Total number of IPv4 scanning attackers.
IP address	IPv4 address of the attacker.
VPN instance	MPLS L3VPN instance to which the attacker's IPv4 address belongs. If the IPv4 address is on the public network, this field displays hyphens (--).
DS-Lite tunnel peer	This field is not supported in the current software version. IPv6 address of the DS-Lite tunnel peer. If the device is the AFTR of a DS-Lite tunnel, this field displays the IPv6 address of the B4 element from which the packet comes. In other situations, this field displays hyphens (--).
Detected on	Where the attack is detected: the device (Local).
Duration(min)	The amount of time the attack lasts, in minutes.

Related commands

display attack-defense scan victim ip

scan detect

display attack-defense scan attacker ipv6

Use display attack-defense scan attacker ipv6 to display information about IPv6 scanning attackers.

Syntax

In standalone mode:

display attack-defense scan attacker ipv6 [ [ local ] [ slot slot-number ] ] [ count ]

In IRF mode:

display attack-defense scan attacker ipv6 [ [ local ] [ chassis chassis-number slot slot-number ] ] [ count ]

Views

Any view

Predefined user roles

network-admin

network-operator

mdc-admin

mdc-operator

Parameters

local: Specifies the device.

slot slot-number: Specifies a card by its slot number. This option is available only when you specify the device. If you do not specify a card, this command displays information about IPv6 scanning attackers for all cards. (In standalone mode.)

chassis chassis-number slot slot-number: Specifies a card on an IRF member device. The chassis-number argument represents the member ID of the IRF member device. The slot-number argument represents the slot number of the card. This option is available only when you specify the device. If you do not specify a card, this command displays information about IPv6 scanning attackers for all cards. (In IRF mode.)

Usage guidelines

If you do not specify any parameters, this command displays information about all IPv6 scanning attackers.

Examples

# (In standalone mode.) Display information about all IPv6 scanning attackers.

<Sysname> display attack-defense scan attacker ipv6

Slot 1:

IPv6 address VPN instance Detected on Duration(min)

1002::20 -- Local 782

Slot 2:

IPv6 address VPN instance Detected on Duration(min)

# (In standalone mode.) Display the number of IPv6 scanning attackers.

<Sysname> display attack-defense scan attacker ipv6 count

Slot 1:

Totally 1 attackers.

Slot 2:

Totally 0 attackers.

Table 8 Command output

Field	Description
Totally 1 attackers	Total number of IPv6 scanning attackers.
IPv6 address	IPv6 address of the attacker.
VPN instance	MPLS L3VPN instance to which the attacker IPv6 address belongs. If the attacker IPv6 address is on the public network, this field displays hyphens (--).
Detected on	Where the attack is detected: the device (Local).
Duration(min)	The amount of time the attack lasts, in minutes.

Related commands

display attack-defense scan victim ipv6

scan detect

display attack-defense scan victim ip

Use display attack-defense scan victim ip to display information about IPv4 scanning attack victims.

Syntax

In standalone mode:

display attack-defense scan victim ip [ [ local ] [ slot slot-number ] ] [ count ]

In IRF mode:

display attack-defense scan victim ip [ [ local ] [ chassis chassis-number slot slot-number ] ] [ count ]

Views

Any view

Predefined user roles

network-admin

network-operator

mdc-admin

mdc-operator

Parameters

local: Specifies the device.

chassis chassis-number slot slot-number: Specifies a card on an IRF member device. The chassis-number argument represents the member ID of the IRF member device. The slot-number argument represents the slot number of the card. This option is available only when you specify the device. If you do not specify a card, this command displays information about IPv4 scanning attack victims for all cards. (In IRF mode.)

Usage guidelines

If you do not specify any parameters, this command displays information about all IPv4 scanning attack victims.

Examples

# (In standalone mode.) Display information about all IPv4 scanning attack victims.

<Sysname> display attack-defense scan victim ip

Slot 1:

IP address VPN instance Detected on Duration(min)

192.168.24.82 -- Local 782

Slot 2:

IP address VPN instance Detected on Duration(min)

# (In standalone mode.) Display the number of IPv4 scanning attack victims.

<Sysname> display attack-defense scan victim ip count

Slot 1:

Totally 1 victim IP addresses.

Slot 2:

Totally 0 victim IP addresses.

Table 9 Command output

Field	Description
Totally 1 victim IP addresses	Total number of IPv4 scanning attack victims.
IP address	IPv4 address of the victim.
VPN instance	MPLS L3VPN instance to which the victim IPv4 address belongs. If the victim IPv4 address is on the public network, this field displays hyphens (--).
Detected on	Where the attack is detected: the device (Local).
Duration(min)	The amount of time the attack lasts, in minutes.

Related commands

display attack-defense scan attacker ip

scan detect

display attack-defense scan victim ipv6

Use display attack-defense scan victim ipv6 to display information about IPv6 scanning attack victims.

Syntax

In standalone mode:

display attack-defense scan victim ipv6 [ [ local ] [ slot slot-number ] ] [ count ]

In IRF mode:

display attack-defense scan victim ipv6 [ [ local ] [ chassis chassis-number slot slot-number ] ] [ count ]

Views

Any view

Predefined user roles

network-admin

network-operator

mdc-admin

mdc-operator

Parameters

local: Specifies the device.

slot slot-number: Specifies a card by its slot number. This option is available only when you specify the device. If you do not specify a card, this command displays information about IPv6 scanning attack victims for all cards. (In standalone mode.)

chassis chassis-number slot slot-number: Specifies a card on an IRF member device. The chassis-number argument represents the member ID of the IRF member device. The slot-number argument represents the slot number of the card. This option is available only when you specify the device. If you do not specify a card, this command displays information about IPv6 scanning attack victims for all cards. (In IRF mode.)

Usage guidelines

If you do not specify any parameters, this command displays information about all IPv6 scanning attack victims.

Examples

# (In standalone mode.) Display information about all IPv6 scanning attack victims.

<Sysname> display attack-defense scan victim ipv6

Slot 1:

IPv6 address VPN instance Detected on Duration(min)

1002::20 -- Local 28

Slot 2:

IPv6 address VPN instance Detected on Duration(min)

# (In standalone mode.) Display the number of IPv6 scanning attack victims.

<Sysname> display attack-defense scan victim ipv6 count

Slot 1:

Totally 1 victim IP addresses.

Slot 2:

Totally 0 victim IP addresses.

Table 10 Command output

Field	Description
Totally 1 victim IP addresses	Total number of IPv6 scanning attack victims.
IPv6 address	IPv6 address of the victim.
VPN instance	MPLS L3VPN instance to which the victim IPv6 address belongs. If the victim IPv6 address is on the public network, this field displays hyphens (--).
Detected on	Where the attack is detected: the device (Local).
Duration(min)	The amount of time the attack lasts, in minutes.

Related commands

display attack-defense scan attacker ipv6

scan detect

display attack-defense statistics local

Use display attack-defense statistics local to display attack detection and prevention statistics for the device.

Syntax

In standalone mode:

display attack-defense statistics local [ slot slot-number ]

In IRF mode:

display attack-defense statistics local [ chassis chassis-number slot slot-number ]

Views

Any view

Predefined user roles

network-admin

network-operator

mdc-admin

mdc-operator

Parameters

slot slot-number: Specifies a card by its slot number. If you do not specify a card, this command displays attack detection and prevention statistics for all cards. (In standalone mode.)

chassis chassis-number slot slot-number: Specifies a card on an IRF member device. The chassis-number argument represents the member ID of the IRF member device. The slot-number argument represents the slot number of the card. If you do not specify a card, this command displays attack detection and prevention statistics for all cards. (In IRF mode.)

Examples

# (In standalone mode.) Display attack detection and prevention statistics for the device.

<Sysname> display attack-defense statistics local

Attack policy name: abc

Slot 1:

Scan attack defense statistics:

AttackType AttackTimes Dropped

Port scan 2 23

IP sweep 3 33

Distribute port scan 1 10

Flood attack defense statistics:

AttackType AttackTimes Dropped

SYN flood 1 0

ACK flood 1 0

SYN-ACK flood 3 5000

RST flood 2 0

FIN flood 2 0

UDP flood 1 0

ICMP flood 1 0

ICMPv6 flood 1 0

DNS flood 1 0

HTTP flood 1 0

Signature attack defense statistics:

AttackType AttackTimes Dropped

IP option record route 1 100

IP option security 2 0

IP option stream ID 3 0

IP option internet timestamp 4 1

IP option loose source routing 5 0

IP option strict source routing 6 0

IP option route alert 3 0

Fragment 1 0

Impossible 1 1

Teardrop 1 1

Tiny fragment 1 0

IP options abnormal 3 0

Smurf 1 0

Ping of death 1 0

Traceroute 1 0

Large ICMP 1 0

TCP NULL flag 1 0

TCP all flags 1 0

TCP SYN-FIN flags 1 0

TCP FIN only flag 1 0

TCP invalid flag 1 0

TCP Land 1 0

Winnuke 1 0

UDP Bomb 1 0

Snork 1 0

Fraggle 1 0

Large ICMPv6 1 0

ICMP echo request 1 0

ICMP echo reply 1 0

ICMP source quench 1 0

ICMP destination unreachable 1 0

ICMP redirect 2 0

ICMP time exceeded 3 0

ICMP parameter problem 4 0

ICMP timestamp request 5 0

ICMP timestamp reply 6 0

ICMP information request 7 0

ICMP information reply 4 0

ICMP address mask request 2 0

ICMP address mask reply 1 0

ICMPv6 echo request 1 1

ICMPv6 echo reply 1 1

ICMPv6 group membership query 1 0

ICMPv6 group membership report 1 0

ICMPv6 group membership reduction 1 0

ICMPv6 destination unreachable 1 0

ICMPv6 time exceeded 1 0

ICMPv6 parameter problem 1 0

ICMPv6 packet too big 1 0

Slot 2:

Scan attack defense statistics:

AttackType AttackTimes Dropped

Port scan 4 46

IP sweep 2 28

Distribute port scan 1 10

Flood attack defense statistics:

AttackType AttackTimes Dropped

SYN flood 1 0

ACK flood 1 0

SYN-ACK flood 2 4200

RST flood 2 0

FIN flood 2 20

UDP flood 1 0

ICMP flood 1 0

ICMPv6 flood 1 0

DNS flood 1 0

HTTP flood 1 0

Signature attack defense statistics:

AttackType AttackTimes Dropped

IP option record route 2 230

IP option security 2 0

IP option stream ID 3 0

IP option internet timestamp 4 1

IP option loose source routing 5 0

IP option strict source routing 2 0

IP option route alert 3 12

Fragment 1 0

Impossible 1 1

Teardrop 1 1

Tiny fragment 1 0

IP options abnormal 3 0

Smurf 1 0

Ping of death 1 0

Traceroute 1 0

Large ICMP 1 0

TCP NULL flag 1 0

TCP all flags 1 0

TCP SYN-FIN flags 1 0

TCP FIN only flag 1 0

TCP invalid flag 1 0

TCP Land 1 0

Winnuke 1 0

UDP Bomb 1 0

Snork 1 0

Fraggle 1 0

Large ICMPv6 1 0

ICMP echo request 1 0

ICMP echo reply 1 0

ICMP source quench 1 0

ICMP destination unreachable 1 0

ICMP redirect 2 3

ICMP time exceeded 3 0

ICMP parameter problem 4 0

ICMP timestamp request 5 0

ICMP timestamp reply 6 0

ICMP information request 7 0

ICMP information reply 4 0

ICMP address mask request 2 0

ICMP address mask reply 1 0

ICMPv6 echo request 1 1

ICMPv6 echo reply 1 1

ICMPv6 group membership query 1 0

ICMPv6 group membership report 1 0

ICMPv6 group membership reduction 1 0

ICMPv6 destination unreachable 1 0

ICMPv6 time exceeded 1 0

ICMPv6 parameter problem 1 0

ICMPv6 packet too big 1 0

Table 11 Command output

Field	Description
AttackType	Type of the attack.
AttackTimes	Number of times that the attack occurred. This command output displays only attacks that are detected.
Dropped	Number of dropped packets.
ICMPv6 flood	ICMPv6 flood attack. This field is not displayed when no ICMPv6 flood attack is detected.
Large ICMPv6	Large ICMPv6 attack. This field is not displayed when no large ICMPv6 attack is detected.
ICMPv6 echo request	ICMPv6 echo request attack. This field is not displayed when no ICMPv6 echo request attack is detected.
ICMPv6 echo reply	ICMPv6 echo reply attack. This field is not displayed when no ICMPv6 echo reply attack is detected.
ICMPv6 group membership query	ICMPv6 group membership query attack. This field is not displayed when no ICMPv6 group membership query attack is detected.
ICMPv6 group membership report	ICMPv6 group membership report attack. This field is not displayed when no ICMPv6 group membership report attack is detected.
ICMPv6 group membership reduction	ICMPv6 group membership reduction attack. This field is not displayed when no ICMPv6 group membership reduction attack is detected.
ICMPv6 destination unreachable	ICMPv6 destination unreachable attack. This field is not displayed when no ICMPv6 destination unreachable attack is detected.
ICMPv6 time exceeded	ICMPv6 time exceeded attack. This field is not displayed when no ICMPv6 time exceeded attack is detected.
ICMPv6 parameter problem	ICMPv6 parameter problem attack. This field is not displayed when no ICMPv6 parameter problem attack is detected.
ICMPv6 packet too big	ICMPv6 packet too big attack. This field is not displayed when no ICMPv6 packet too big attack is detected.

Related commands

reset attack-defense statistics local

dns-flood action

Use dns-flood action to specify global actions against DNS flood attacks.

Use undo dns-flood action to restore the default.

Syntax

dns-flood action { drop | logging } *

undo dns-flood action

Default

No global action is specified for DNS flood attacks.

Views

Attack defense policy view

Predefined user roles

network-admin

mdc-admin

Parameters

drop: Drops subsequent DNS packets destined for the victim IP addresses.

logging: Enables logging for DNS flood attack events.

Examples

# Specify drop as the global action against DNS flood attacks in attack defense policy atk-policy-1.

<Sysname> system-view

[Sysname] attack-defense policy atk-policy-1

[Sysname-attack-defense-policy-atk-policy-1] dns-flood action drop

Related commands

dns-flood detect

dns-flood detect non-specific

dns-flood threshold

dns-flood detect

Use dns-flood detect to configure IP address-specific DNS flood attack detection.

Use undo dns-flood detect to remove the IP address-specific DNS flood attack detection configuration.

Syntax

dns-flood detect { ip ipv4-address | ipv6 ipv6-address } [ vpn-instance vpn-instance-name ] [ port port-list ] [ threshold threshold-value ] [ action { { drop | logging } * | none } ]

undo dns-flood detect { ip ipv4-address | ipv6 ipv6-address } [ vpn-instance vpn-instance-name ]

Default

IP address-specific DNS flood attack detection is not configured.

Views

Attack defense policy view

Predefined user roles

network-admin

mdc-admin

Parameters

ip ipv4-address: Specifies the IPv4 address to be protected. The ip-address argument cannot be all 1s or 0s.

ipv6 ipv6-address: Specifies the IPv6 address to be protected.

port port-list: Specifies a space-separated list of up to 65535 port number items. Each item specifies a port by its port number or a range of ports in the form of start-port-number to end-port-number. The end-port-number cannot be smaller than the start-port-number. If you do not specify this option, the global ports apply.

threshold threshold-value: Specifies the threshold for triggering DNS flood attack prevention. The value range is 1 to 1000000 in units of DNS packets sent to the specified IP address per second.

action: Specifies the actions when a DNS flood attack is detected. If no action is specified, the global actions set by the dns-flood action command apply.

drop: Drops subsequent DNS packets destined for the protected IP address.

logging: Enables logging for DNS flood attack events.

none: Takes no action.

Usage guidelines

With DNS flood attack detection configured for an IP address, the device is in attack detection state. When the sending rate of DNS packets to the IP address reaches the threshold, the device enters prevention state and takes the specified actions. When the rate is below the silence threshold (three-fourths of the threshold), the device returns to the attack detection state.

You can configure DNS flood attack detection for multiple IP addresses in one attack defense policy.

Examples

# Configure DNS flood attack detection for 192.168.1.2 in attack defense policy atk-policy-1.

<Sysname> system-view

[Sysname] attack-defense policy atk-policy-1

[Sysname-attack-defense-policy-atk-policy-1] dns-flood detect ip 192.168.1.2 port 53 threshold 2000

Related commands

dns-flood action

dns-flood detect non-specific

dns-flood threshold

dns-flood port

dns-flood detect non-specific

Use dns-flood detect non-specific to enable global DNS flood attack detection.

Use undo dns-flood detect non-specific to disable global DNS flood attack detection.

Syntax

dns-flood detect non-specific

undo dns-flood detect non-specific

Default

Global DNS flood attack detection is disabled.

Views

Attack defense policy view

Predefined user roles

network-admin

mdc-admin

Usage guidelines

The global DNS flood attack detection applies to all IP addresses except for those specified by the dns-flood detect command. The global detection uses the global trigger threshold set by the dns-flood threshold command and global actions specified by the dns-flood action command.

Examples

# Enable global DNS flood attack detection in attack defense policy atk-policy-1.

<Sysname> system-view

[Sysname] attack-defense policy atk-policy-1

[Sysname-attack-defense-policy-atk-policy-1] dns-flood detect non-specific

Related commands

dns-flood action

dns-flood detect

dns-flood threshold

dns-flood port

Use dns-flood port to specify the global ports to be protected against DNS flood attacks.

Use undo dns-flood port to restore the default.

Syntax

dns-flood port port-list

undo dns-flood port

Default

The global DNS flood attack prevention protects port 53.

Views

Attack defense policy view

Predefined user roles

network-admin

mdc-admin

Parameters

port-list: Specifies a space-separated list of up to 65535 port number items. Each item specifies a port by its port number or a range of ports in the form of start-port-number to end-port-number. The end-port-number cannot be smaller than the start-port-number.

Usage guidelines

The device detects only DNS packets destined for the specified ports.

The global ports apply to global DNS flood attack detection and IP address-specific DNS flood attack detection with no port specified.

Examples

# Specify the ports 53 and 61000 as the global ports to be protected against DNS flood attacks in attack defense policy atk-policy-1.

<Sysname> system-view

[Sysname] attack-defense policy atk-policy-1

[Sysname-attack-defense-policy-atk-policy-1] dns-flood port 53 61000

Related commands

dns-flood action

dns-flood detect

dns-flood detect non-specific

dns-flood threshold

Use dns-flood threshold to set the global threshold for triggering DNS flood attack prevention.

Use undo dns-flood threshold to restore the default.

Syntax

dns-flood threshold threshold-value

undo dns-flood threshold

Default

The global threshold is 1000 for triggering DNS flood attack prevention.

Views

Attack defense policy view

Predefined user roles

network-admin

mdc-admin

Parameters

threshold-value: Specifies the threshold value. The value range is 1 to 1000000 in units of DNS packets sent to an IP address per second.

Usage guidelines

With global DNS flood attack detection configured, the device is in attack detection state. When the sending rate of DNS packets to an IP address reaches the threshold, the device enters prevention state and takes the specified actions. When the rate is below the silence threshold (three-fourths of the threshold), the device returns to the attack detection state.

The global threshold applies to global DNS flood attack detection. Adjust the threshold according to the application scenarios. If the number of DNS packets sent to a protected DNS server is normally large, set a large threshold. A small threshold might affect the server services. For a network that is unstable or susceptible to attacks, set a small threshold.

Examples

# Set the global threshold to 100 for triggering DNS flood attack prevention in attack defense policy atk-policy-1.

<Sysname> system-view

[Sysname] attack-defense policy atk-policy-1

[Sysname-attack-defense-policy-atk-policy-1] dns-flood threshold 100

Related commands

dns-flood action

dns-flood detect

dns-flood detect non-specific

exempt acl

Use exempt acl to configure attack detection exemption.

Use undo exempt acl to restore the default.

Syntax

exempt acl [ ipv6 ] { acl-number | name acl-name }

undo exempt acl [ ipv6 ]

Default

Attack detection exemption is not configured.

Views

Attack defense policy view

Predefined user roles

network-admin

mdc-admin

Parameters

ipv6: Specifies an IPv6 ACL. To specify an IPv4 ACL, do not use this keyword.

acl-number: Specifies an ACL by its number:

· 2000 to 2999 for basic ACLs.

· 3000 to 3999 for advanced ACLs.

name acl-name: Specifies an ACL by its name. The acl-name argument is a case-insensitive string of 1 to 63 characters. It must start with an English letter and to avoid confusion, it cannot be all.

Usage guidelines

The attack defense policy uses an ACL to identify exempted packets. The policy does not check the packets permitted by the ACL. You can configure the ACL to identify packets from trusted hosts. The exemption feature reduces the false alarm rate and improves packet processing efficiency.

If an ACL is used for attack detection exemption, only the following match criteria in the ACL permit rules take effect:

· Source IP address.

· Destination IP address.

· Source port.

· Destination port.

· Protocol.

· L3VPN instance.

· The fragment keyword for matching non-first fragments.

If the specified ACL does not exist or does not contain a rule, attack detection exemption does not take effect.

Examples

# Configure an ACL to permit packets sourced from 1.1.1.1. Configure attack detection exemption for packets matching the ACL in attack defense policy atk-policy-1.

<Sysname> system-view

[Sysname] acl basic 2001

[Sysname-acl-ipv4-basic-2001] rule permit source 1.1.1.1 0

[Sysname-acl-ipv4-basic-2001] quit

[Sysname] attack-defense policy atk-policy-1

[attack-defense-policy-atk-policy-1] exempt acl 2001

Related commands

attack-defense policy

fin-flood action

Use fin-flood action to specify global actions against FIN flood attacks.

Use undo fin-flood action to restore the default.

Syntax

fin-flood action { drop | logging } *

undo fin-flood action

Default

No global action is specified for FIN flood attacks.

Views

Attack defense policy view

Predefined user roles

network-admin

mdc-admin

Parameters

drop: Drops subsequent FIN packets destined for the victim IP addresses.

logging: Enables logging for FIN flood attack events.

Examples

# Specify drop as the global action against FIN flood attacks in attack defense policy atk-policy-1.

<Sysname> system-view

[Sysname] attack-defense policy atk-policy-1

[Sysname-attack-defense-policy-atk-policy-1] fin-flood action drop

Related commands

fin-flood detect

fin-flood detect non-specific

fin-flood threshold

fin-flood detect

Use fin-flood detect to configure IP address-specific FIN flood attack detection.

Use undo fin-flood detect to remove the IP address-specific FIN flood attack detection configuration.

Syntax

fin-flood detect { ip ipv4-address | ipv6 ipv6-address } [ vpn-instance vpn-instance-name ] [ threshold threshold-value ] [ action { { drop | logging } * | none } ]

undo fin-flood detect { ip ipv4-address | ipv6 ipv6-address } [ vpn-instance vpn-instance-name ]

Default

IP address-specific FIN flood attack detection is not configured.

Views

Attack defense policy view

Predefined user roles

network-admin

mdc-admin

Parameters

ip ipv4-address: Specifies the IPv4 address to be protected. The ip-address argument cannot be all 1s or 0s.

ipv6 ipv6-address: Specifies the IPv6 address to be protected.

threshold threshold-value: Specifies the threshold for triggering FIN flood attack prevention. The value range is 1 to 1000000 in units of FIN packets sent to the specified IP address per second.

action: Specifies the actions when a FIN flood attack is detected. If no action is specified, the global actions set by the fin-flood action command apply.

drop: Drops subsequent FIN packets destined for the protected IP address.

logging: Enables logging for FIN flood attack events.

none: Takes no action.

Usage guidelines

With FIN flood attack detection configured for an IP address, the device is in attack detection state. When the sending rate of FIN packets to the IP address reaches the threshold, the device enters prevention state and takes the specified actions. When the rate is below the silence threshold (three-fourths of the threshold), the device returns to the attack detection state.

You can configure FIN flood attack detection for multiple IP addresses in one attack defense policy.

Examples

# Configure FIN flood attack detection for 192.168.1.2 in attack defense policy atk-policy-1.

<Sysname> system-view

[Sysname] attack-defense policy atk-policy-1

[Sysname-attack-defense-policy-atk-policy-1] fin-flood detect ip 192.168.1.2 threshold 2000

Related commands

fin-flood action

fin-flood detect non-specific

fin-flood threshold

fin-flood detect non-specific

Use fin-flood detect non-specific to enable global FIN flood attack detection.

Use undo fin-flood detect non-specific to disable global FIN flood attack detection.

Syntax

fin-flood detect non-specific

undo fin-flood detect non-specific

Default

Global FIN flood attack detection is disabled.

Views

Attack defense policy view

Predefined user roles

network-admin

mdc-admin

Usage guidelines

The global FIN flood attack detection applies to all IP addresses except for those specified by the fin-flood detect command. The global detection uses the global trigger threshold set by the fin-flood threshold command and global actions specified by the fin-flood action command.

Examples

# Enable global FIN flood attack detection in attack defense policy atk-policy-1.

<Sysname> system-view

[Sysname] attack-defense policy atk-policy-1

[Sysname-attack-defense-policy-atk-policy-1] fin-flood detect non-specific

Related commands

fin-flood action

fin-flood detect

fin-flood threshold

Use fin-flood threshold to set the global threshold for triggering FIN flood attack prevention.

Use undo fin-flood threshold to restore the default.

Syntax

fin-flood threshold threshold-value

undo fin-flood threshold

Default

The global threshold is 1000 for triggering FIN flood attack prevention.

Views

Attack defense policy view

Predefined user roles

network-admin

mdc-admin

Parameters

threshold-value: Specifies the threshold value. The value range is 1 to 1000000 in units of FIN packets sent to an IP address per second.

Usage guidelines

With global FIN flood attack detection configured, the device is in attack detection state. When the sending rate of FIN packets to an IP address reaches the threshold, the device enters prevention state and takes the specified actions. When the rate is below the silence threshold (three-fourths of the threshold), the device returns to the attack detection state.

The global threshold applies to global FIN flood attack detection. Adjust the threshold according to the application scenarios. If the number of FIN packets sent to a protected server, such as an HTTP or FTP server, is normally large, set a large threshold. A small threshold might affect the server services. For a network that is unstable or susceptible to attacks, set a small threshold.

Examples

# Set the global threshold to 100 for triggering FIN flood attack prevention in attack defense policy atk-policy-1.

<Sysname> system-view

[Sysname] attack-defense policy atk-policy-1

[Sysname-attack-defense-policy-atk-policy-1] fin-flood threshold 100

Related commands

fin-flood action

fin-flood detect

fin-flood detect non-specific

http-flood action

Use http-flood action to specify global actions against HTTP flood attacks.

Use undo http-flood action to restore the default.

Syntax

http-flood action { drop | logging } *

undo http-flood action

Default

No global action is specified for HTTP flood attacks.

Views

Attack defense policy view

Predefined user roles

network-admin

mdc-admin

Parameters

drop: Drops subsequent HTTP packets destined for the victim IP addresses.

logging: Enables logging for HTTP flood attack events.

Examples

# Specify drop as the global action against HTTP flood attacks in attack defense policy atk-policy-1.

<Sysname> system-view

[Sysname] attack-defense policy atk-policy-1

[Sysname-attack-defense-policy-atk-policy-1] http-flood action drop

Related commands

http-flood detect

http-flood detect non-specific

http-flood threshold

http-flood detect

Use http-flood detect to configure IP address-specific HTTP flood attack detection.

Use undo http-flood detect to remove the IP address-specific HTTP flood attack detection configuration.

Syntax

http-flood detect { ip ipv4-address | ipv6 ipv6-address } [ vpn-instance vpn-instance-name ] [ port port-list ] [ threshold threshold-value ] [ action { { drop | logging } * | none } ]

undo http-flood detect { ip ipv4-address | ipv6 ipv6-address } [ vpn-instance vpn-instance-name ]

Default

IP address-specific HTTP flood attack detection is not configured.

Views

Attack defense policy view

Predefined user roles

network-admin

mdc-admin

Parameters

ip ipv4-address: Specifies the IPv4 address to be protected. The ip-address argument cannot be all 1s or 0s.

ipv6 ipv6-address: Specifies the IPv6 address to be protected.

threshold threshold-value: Specifies the threshold for triggering HTTP flood attack prevention. The value range is 1 to 1000000 in units of HTTP packets sent to the specified IP address per second.

action: Specifies the actions when an HTTP flood attack is detected. If no action is specified, the global actions set by the http-flood action command apply.

drop: Drops subsequent HTTP packets destined for the protected IP address.

logging: Enables logging for HTTP flood attack events.

none: Takes no action.

Usage guidelines

With HTTP flood attack detection configured for an IP address, the device is in attack detection state. When the sending rate of HTTP packets to the IP address reaches the threshold, the device enters prevention state and takes the specified actions. When the rate is below the silence threshold (three-fourths of the threshold), the device returns to the attack detection state.

You can configure HTTP flood attack detection for multiple IP addresses in one attack defense policy.

Examples

# Configure HTTP flood attack detection for 192.168.1.2 in attack defense policy atk-policy-1.

<Sysname> system-view

[Sysname] attack-defense policy atk-policy-1

[Sysname-attack-defense-policy-atk-policy-1] http-flood detect ip 192.168.1.2 port 80 8080 threshold 2000

Related commands

http-flood action

http-flood detect non-specific

http-flood threshold

http-flood port

http-flood detect non-specific

Use http-flood detect non-specific to enable global HTTP flood attack detection.

Use undo http-flood detect non-specific to disable global HTTP flood attack detection.

Syntax

http-flood detect non-specific

undo http-flood detect non-specific

Default

Global HTTP flood attack detection is disabled.

Views

Attack defense policy view

Predefined user roles

network-admin

mdc-admin

Usage guidelines

The global HTTP flood attack detection applies to all IP addresses except for those specified by the http-flood detect command. The global detection uses the global trigger threshold set by the http-flood threshold command and global actions specified by the http-flood action command.

Examples

# Enable global HTTP flood attack detection in attack defense policy atk-policy-1.

<Sysname> system-view

[Sysname] attack-defense policy atk-policy-1

[Sysname-attack-defense-policy-atk-policy-1] dns-flood detect non-specific

Related commands

http-flood action

http-flood detect

http-flood threshold

http-flood port

Use http-flood port to specify the global ports to be protected against HTTP flood attacks.

Use undo http-flood port to restore the default.

Syntax

http-flood port port-list

undo http-flood port

Default

The global HTTP flood attack prevention protects port 80.

Views

Attack defense policy view

Predefined user roles

network-admin

mdc-admin

Parameters

Usage guidelines

The device detects only HTTP packets destined for the specified ports.

The global ports apply to global HTTP flood attack detection and IP address-specific HTTP flood attack detection with no port specified.

Examples

# Specify the ports 80 and 8080 as the global ports to be protected against HTTP flood attacks in attack the defense policy atk-policy-1.

<Sysname> system-view

[Sysname] attack-defense policy atk-policy-1

[Sysname-attack-defense-policy-atk-policy-1] http-flood port 80 8080

Related commands

http-flood action

http-flood detect

http-flood detect non-specific

http-flood threshold

Use http-flood threshold to set the global threshold for triggering HTTP flood attack prevention.

Use undo http-flood threshold to restore the default.

Syntax

http-flood threshold threshold-value

undo http-flood threshold

Default

The global threshold is 1000 for triggering HTTP flood attack prevention.

Views

Attack defense policy view

Predefined user roles

network-admin

mdc-admin

Parameters

threshold-value: Specifies the threshold value. The value range is 1 to 1000000 in units of HTTP packets sent to an IP address per second.

Usage guidelines

With global HTTP flood attack detection configured, the device is in attack detection state. When the sending rate of HTTP packets to an IP address reaches the threshold, the device enters prevention state and takes the specified actions. When the rate is below the silence threshold (three-fourths of the threshold), the device returns to the attack detection state.

The global threshold applies to global HTTP flood attack detection. Adjust the threshold according to the application scenarios. If the number of HTTP packets sent to a protected HTTP server is normally large, set a large threshold. A small threshold might affect the server services. For a network that is unstable or susceptible to attacks, set a small threshold.

Examples

# Set the global threshold to 100 for triggering HTTP flood attack prevention in attack defense policy atk-policy-1.

<Sysname> system-view

[Sysname] attack-defense policy atk-policy-1

[Sysname-attack-defense-policy-atk-policy-1] http-flood threshold 100

Related commands

http-flood action

http-flood detect

http-flood detect non-specific

icmp-flood action

Use icmp-flood action to specify global actions against ICMP flood attacks.

Use undo icmp-flood action to restore the default.

Syntax

icmp-flood action { drop | logging } *

undo icmp-flood action

Default

No global action is specified for ICMP flood attacks.

Views

Attack defense policy view

Predefined user roles

network-admin

mdc-admin

Parameters

drop: Drops subsequent ICMP packets destined for the victim IP addresses.

logging: Enables logging for ICMP flood attack events.

Examples

# Specify drop as the global action against ICMP flood attacks in attack defense policy atk-policy-1.

<Sysname> system-view

[Sysname] attack-defense policy atk-policy-1

[Sysname-attack-defense-policy-atk-policy-1] icmp-flood action drop

Related commands

icmp-flood detect non-specific

icmp-flood detect ip

icmp-flood threshold

icmp-flood detect ip

Use icmp-flood detect ip to configure IP address-specific ICMP flood attack detection.

Use undo icmp-flood detect ip to remove the IP address-specific ICMP flood attack detection configuration.

Syntax

icmp-flood detect ip ip-address [ vpn-instance vpn-instance-name ] [ threshold threshold-value ] [ action { { drop | logging } * | none } ]

undo icmp-flood detect ip ip-address [ vpn-instance vpn-instance-name ]

Default

IP address-specific ICMP flood attack detection is not configured.

Views

Attack defense policy view

Predefined user roles

network-admin

mdc-admin

Parameters

ip-address: Specifies the IPv4 address to be protected. The ip-address argument cannot be all 1s or 0s.

threshold threshold-value: Specifies the threshold for triggering ICMP flood attack prevention. The value range is 1 to 1000000 in units of ICMP packets sent to the specified IP address per second.

action: Specifies the actions when an ICMP flood attack is detected. If no action is specified, the global actions set by the icmp-flood action command apply.

drop: Drops subsequent ICMP packets destined for the protected IP address.

logging: Enables logging for ICMP flood attack events.

none: Takes no action.

Usage guidelines

With ICMP flood attack detection configured for an IP address, the device is in attack detection state. When the sending rate of ICMP packets to the IP address reaches the threshold, the device enters prevention state and takes the specified actions. When the rate is below the silence threshold (three-fourths of the threshold), the device returns to the attack detection state.

You can configure ICMP flood attack detection for multiple IP addresses in one attack defense policy.

Examples

# Configure ICMP flood attack detection for 192.168.1.2 in attack defense policy atk-policy-1.

<Sysname> system-view

[Sysname] attack-defense policy atk-policy-1

[Sysname-attack-defense-policy-atk-policy-1] icmp-flood detect ip 192.168.1.2 threshold 2000

Related commands

icmp-flood action

icmp-flood detect non-specific

icmp-flood threshold

icmp-flood detect non-specific

Use icmp-flood detect non-specific to enable global ICMP flood attack detection.

Use undo icmp-flood detect non-specific to disable global ICMP flood attack detection.

Syntax

icmp-flood detect non-specific

undo icmp-flood detect non-specific

Default

Global ICMP flood attack detection is disabled.

Views

Attack defense policy view

Predefined user roles

network-admin

mdc-admin

Usage guidelines

The global ICMP flood attack detection applies to all IP addresses except for those specified by the icmp-flood detect ip command. The global detection uses the global trigger threshold set by the icmp-flood threshold command and global actions specified by the icmp-flood action command.

Examples

# Enable global ICMP flood attack detection in attack defense policy atk-policy-1.

<Sysname> system-view

[Sysname] attack-defense policy atk-policy-1

[Sysname-attack-defense-policy-atk-policy-1] icmp-flood detect non-specific

Related commands

icmp-flood action

icmp-flood detect ip

icmp-flood threshold

Use icmp-flood threshold to set the global threshold for triggering ICMP flood attack prevention.

Use undo icmp-flood threshold to restore the default.

Syntax

icmp-flood threshold threshold-value

undo icmp-flood threshold

Default

The global threshold is 1000 for triggering ICMP flood attack prevention.

Views

Attack defense policy view

Predefined user roles

network-admin

mdc-admin

Parameters

threshold-value: Specifies the threshold value. The value range is 1 to 1000000 in units of ICMP packets sent to an IP address per second.

Usage guidelines

With global ICMP flood attack detection configured, the device is in attack detection state. When the sending rate of ICMP packets to an IP address reaches the threshold, the device enters prevention state and takes the specified actions. When the rate is below the silence threshold (three-fourths of the threshold), the device returns to the attack detection state.

The global threshold applies to global ICMP flood attack detection. Adjust the threshold according to the application scenarios. If the number of ICMP packets sent to a protected server, such as an HTTP or FTP server, is normally large, set a large threshold. A small threshold might affect the server services. For a network that is unstable or susceptible to attacks, set a small threshold.

Examples

# Set the global threshold to 100 for triggering ICMP flood attack prevention in attack defense policy atk-policy-1.

<Sysname> system-view

[Sysname] attack-defense policy atk-policy-1

[Sysname-attack-defense-policy-atk-policy-1] icmp-flood threshold 100

Related commands

icmp-flood action

icmp-flood detect ip

icmp-flood detect non-specific

icmpv6-flood action

Use icmpv6-flood action to specify global actions against ICMPv6 flood attacks.

Use undo icmpv6-flood action to restore the default.

Syntax

icmpv6-flood action { drop | logging } *

undo icmpv6-flood action

Default

No global action is specified for ICMPv6 flood attacks.

Views

Attack defense policy view

Predefined user roles

network-admin

mdc-admin

Parameters

drop: Drops subsequent ICMPv6 packets destined for the victim IP addresses.

logging: Enables logging for ICMPv6 flood attack events.

Examples

# Specify drop as the global action against ICMPv6 flood attacks in attack defense policy atk-policy-1.

<Sysname> system-view

[Sysname] attack-defense policy atk-policy-1

[Sysname-attack-defense-policy-atk-policy-1] icmpv6-flood action drop

Related commands

icmpv6-flood detect ipv6

icmpv6-flood detect non-specific

icmpv6-flood threshold

icmpv6-flood detect ipv6

Use icmpv6-flood detect ipv6 to configure IPv6 address-specific ICMPv6 flood attack detection.

Use undo icmpv6-flood detect ipv6 to remove the IPv6 address-specific ICMPv6 flood attack detection configuration.

Syntax

icmpv6-flood detect ipv6 ipv6-address [ vpn-instance vpn-instance-name ] [ threshold threshold-value ] [ action { { drop | logging } * | none } ]

undo icmpv6-flood detect ipv6 ipv6-address [ vpn-instance vpn-instance-name ]

Default

IPv6 address-specific ICMPv6 flood attack detection is not configured.

Views

Attack defense policy view

Predefined user roles

network-admin

mdc-admin

Parameters

Ipv6-address: Specifies the IPv6 address to be protected.

threshold threshold-value: Specifies the threshold for triggering ICMPv6 flood attack prevention. The value range is 1 to 1000000 in units of ICMPv6 packets sent to the specified IP address per second.

action: Specifies the actions when an ICMPv6 flood attack is detected. If no action is specified, the global actions set by the icmpv6-flood action command apply.

drop: Drops subsequent ICMPv6 packets destined for the protected IPv6 address.

logging: Enables logging for ICMPv6 flood attack events.

none: Takes no action.

Usage guidelines

With ICMPv6 flood attack detection configured for an IPv6 address, the device is in attack detection state. When the sending rate of ICMPv6 packets to the IPv6 address reaches the threshold, the device enters prevention state and takes the specified actions. When the rate is below the silence threshold (three-fourths of the threshold), the device returns to the attack detection state.

You can configure ICMPv6 flood attack detection for multiple IPv6 addresses in one attack defense policy.

Examples

# Configure ICMPv6 flood attack detection for 2012::12 in attack defense policy atk-policy-1.

<Sysname> system-view

[Sysname] attack-defense policy atk-policy-1

[Sysname-attack-defense-policy-atk-policy-1] icmpv6-flood detect ipv6 2012::12 threshold 2000

Related commands

icmpv6-flood action

icmpv6-flood detect non-specific

icmpv6-flood threshold

icmpv6-flood detect non-specific

Use icmpv6-flood detect non-specific to enable global ICMPv6 flood attack detection.

Use undo icmpv6-flood detect non-specific to disable global ICMPv6 flood attack detection.

Syntax

icmpv6-flood detect non-specific

undo icmpv6-flood detect non-specific

Default

Global ICMPv6 flood attack detection is disabled.

Views

Attack defense policy view

Predefined user roles

network-admin

mdc-admin

Usage guidelines

The global ICMPv6 flood attack detection applies to all IPv6 addresses except for those specified by the icmpv6-flood detect ipv6 command. The global detection uses the global trigger threshold set by the icmpv6-flood threshold command and global actions specified by the icmpv6-flood action command.

Examples

# Enable global ICMPv6 flood attack detection in attack defense policy atk-policy-1.

<Sysname> system-view

[Sysname] attack-defense policy atk-policy-1

[Sysname-attack-defense-policy-atk-policy-1] icmpv6-flood detect non-specific

Related commands

icmpv6-flood action

icmpv6-flood detect ipv6

icmpv6-flood threshold

Use icmpv6-flood threshold to set the global threshold for triggering ICMPv6 flood attack prevention.

Use undo icmpv6-flood threshold to restore the default.

Syntax

icmpv6-flood threshold threshold-value

undo icmpv6-flood threshold

Default

The global threshold is 1000 for triggering ICMPv6 flood attack prevention.

Views

Attack defense policy view

Predefined user roles

network-admin

mdc-admin

Parameters

threshold-value: Specifies the threshold value. The value range is 1 to 1000000 in units of ICMPv6 packets sent to an IP address per second.

Usage guidelines

With global ICMPv6 flood attack detection configured, the device is in attack detection state. When the sending rate of ICMPv6 packets to an IPv6 address reaches the threshold, the device enters prevention state and takes the specified actions. When the rate is below the silence threshold (three-fourths of the threshold), the device returns to the attack detection state.

The global threshold applies to global ICMPv6 flood attack detection. Adjust the threshold according to the application scenarios. If the number of ICMPv6 packets sent to a protected server, such as an HTTP or FTP server, is normally large, set a large threshold. A small threshold might affect the server services. For a network that is unstable or susceptible to attacks, set a small threshold.

Examples

# Set the global threshold to 100 for triggering ICMPv6 flood attack prevention in attack defense policy atk-policy-1.

<Sysname> system-view

[Sysname] attack-defense policy atk-policy-1

[Sysname-attack-defense-policy-atk-policy-1] icmpv6-flood threshold 100

Related commands

icmpv6-flood action

icmpv6-flood detect ipv6

icmpv6-flood detect non-specific

reset attack-defense policy flood

Use reset attack-defense policy flood statistics to clear flood attack detection and prevention statistics for protected IP addresses.

Syntax

reset attack-defense policy policy-name flood protected { ip | ipv6 } statistics

Views

User view

Predefined user roles

network-admin

mdc-admin

Parameters

ip: Specifies protected IPv4 addresses.

ipv6: Specifies protected IPv6 addresses.

statistics: Clears flood attack detection and prevention statistics.

Examples

# Clear flood attack detection and prevention statistics for protected IPv4 addresses in attack defense policy abc.

<Sysname> reset attack-defense policy abc flood protected ip statistics

# Clear flood attack detection and prevention statistics for protected IPv6 addresses in attack defense policy abc.

<Sysname> reset attack-defense policy abc flood protected ipv6 statistics

Related commands

display attack-defense policy ip

display attack-defense policy ipv6

reset attack-defense statistics local

Use reset attack-defense statistics local to clear attack detection and prevention statistics for the device.

Syntax

reset attack-defense statistics local

Views

User view

Predefined user roles

network-admin

mdc-admin

Examples

# Clear attack detection and prevention statistics for the device.

<Sysname> reset attack-defense statistics local

Related commands

display attack-defense statistics local

rst-flood action

Use rst-flood action to specify global actions against RST flood attacks.

Use undo rst-flood action to restore the default.

Syntax

rst-flood action { drop | logging } *

undo rst-flood action

Default

No global action is specified for RST flood attacks.

Views

Attack defense policy view

Predefined user roles

network-admin

mdc-admin

Parameters

drop: Drops subsequent RST packets destined for the victim IP addresses.

logging: Enables logging for RST flood attack events.

Examples

# Specify drop as the global action against RST flood attacks in attack defense policy atk-policy-1.

<Sysname> system-view

[Sysname] attack-defense policy atk-policy-1

[Sysname-attack-defense-policy-atk-policy-1] rst-flood action drop

Related commands

rst-flood detect

rst-flood detect non-specific

rst-flood threshold

rst-flood detect

Use rst-flood detect to configure IP address-specific RST flood attack detection.

Use undo rst-flood detect to remove the IP address-specific RST flood attack detection configuration.

Syntax

rst-flood detect { ip ipv4-address | ipv6 ipv6-address } [ vpn-instance vpn-instance-name ] [ threshold threshold-value ] [ action { { drop | logging } * | none } ]

undo rst-flood detect { ip ipv4-address | ipv6 ipv6-address } [ vpn-instance vpn-instance-name ]

Default

IP address-specific RST flood attack detection is not configured.

Views

Attack defense policy view

Predefined user roles

network-admin

mdc-admin

Parameters

ip ipv4-address: Specifies the IPv4 address to be protected. The ip-address argument cannot be all 1s or 0s.

ipv6 ipv6-address: Specifies the IPv6 address to be protected.

threshold threshold-value: Specifies the threshold for triggering RST flood attack prevention. The value range is 1 to 1000000 in units of RST packets sent to the specified IP address per second.

action: Specifies the actions when an RST flood attack is detected. If no action is specified, the global actions set by the rst-flood action command apply.

drop: Drops subsequent RST packets destined for the protected IP address.

logging: Enables logging for RST flood attack events.

none: Takes no action.

Usage guidelines

With RST flood attack detection configured for an IP address, the device is in attack detection state. When the sending rate of RST packets to the IP address reaches the threshold, the device enters prevention state and takes the specified actions. When the rate is below the silence threshold (three-fourths of the threshold), the device considers returns to the attack detection state.

You can configure RST flood attack detection for multiple IP addresses in one attack defense policy.

Examples

# Configure RST flood attack detection for 192.168.1.2 in attack defense policy atk-policy-1.

<Sysname> system-view

[Sysname] attack-defense policy atk-policy-1

[Sysname-attack-defense-policy-atk-policy-1] rst-flood detect ip 192.168.1.2 threshold 2000

Related commands

rst-flood action

rst-flood detect non-specific

rst-flood threshold

rst-flood detect non-specific

Use rst-flood detect non-specific to enable global RST flood attack detection.

Use undo rst-flood detect non-specific to disable global RST flood attack detection.

Syntax

rst-flood detect non-specific

undo rst-flood detect non-specific

Default

Global RST flood attack detection is disabled.

Views

Attack defense policy view

Predefined user roles

network-admin

mdc-admin

Usage guidelines

The global RST flood attack detection applies to all IP addresses except for those specified by the rst-flood detect command. The global detection uses the global trigger threshold set by the rst-flood threshold command and global actions specified by the rst-flood action command.

Examples

# Enable global RST flood attack detection in attack defense policy atk-policy-1.

<Sysname> system-view

[Sysname] attack-defense policy atk-policy-1

[Sysname-attack-defense-policy-atk-policy-1] rst-flood detect non-specific

Related commands

rst-flood action

rst-flood detect

rst-flood threshold

Use rst-flood threshold to set the global threshold for triggering RST flood attack prevention.

Use undo rst-flood threshold to restore the default.

Syntax

rst-flood threshold threshold-value

undo rst-flood threshold

Default

The global threshold is 1000 for triggering RST flood attack prevention.

Views

Attack defense policy view

Predefined user roles

network-admin

mdc-admin

Parameters

threshold-value: Specifies the threshold value. The value range is 1 to 1000000 in units of RST packets sent to an IP address per second.

Usage guidelines

With global RST flood attack detection configured, the device is in attack detection state. When the sending rate of RST packets to an IP address reaches the threshold, the device enters prevention state and takes the specified actions. When the rate is below the silence threshold (three-fourths of the threshold), the device returns to the attack detection state.

The global threshold applies to global RST flood attack detection. Adjust the threshold according to the application scenarios. If the number of RST packets sent to a protected server, such as an HTTP or FTP server, is normally large, set a large threshold. A small threshold might affect the server services. For a network that is unstable or susceptible to attacks, set a small threshold.

Examples

# Set the global threshold to 100 for triggering RST flood attack prevention in attack defense policy atk-policy-1.

<Sysname> system-view

[Sysname] attack-defense policy atk-policy-1

[Sysname-attack-defense-policy-atk-policy-1] rst-flood threshold 100

Related commands

rst-flood action

rst-flood detect

rst-flood detect non-specific

scan detect

Use scan detect to configure scanning attack detection.

Use undo scan detect to remove the scanning attack detection configuration.

Syntax

scan detect level { high | low | medium } action { drop | logging } *

undo scan detect level { high | low | medium }

Default

No scanning attack detection is configured.

Views

Attack defense policy view

Predefined user roles

network-admin

mdc-admin

Parameters

level: Specifies the level of the scanning attack detection.

low: Specifies the low level. This level provides basic scanning attack detection. It has a low false alarm rate but many scanning attacks cannot be detected. Statistics are collected every 60 seconds for the low level detection.

high: Specifies the high level. This level can detect most of the scanning attacks, but has a high false alarm rate. Some packets from active hosts might be considered as attack packets. Statistics are collected every 600 seconds for the high level detection.

medium: Specifies the medium level. Compared with the high and low levels, this level has medium false alarm rate and attack detection accuracy. Statistics are collected every 90 seconds for the medium level detection.

action: Specifies the actions against scanning attacks.

drop: Drops subsequent packets from detected scanning attack sources.

logging: Enables logging for scanning attack events.

Usage guidelines

To collaborate with the IP blacklist feature, make sure the blacklist feature is enabled on the interface to which the attack defense policy is applied.

The aging timer set by the timeout minutes option must be longer than the statistics collection interval.

Examples

# Configure low level scanning attack detection and specify the prevention action as drop in attack defense policy atk-policy-1.

<Sysname> system-view

[Sysname] attack-defense policy atk-policy-1

[Sysname-attack-defense-policy-atk-policy-1] scan detect level low action drop

# Configure scanning attack detection in attack defense policy atk-policy-1. Specify the detection level as low and the prevention actions as block-source and logging. Set the aging time for the dynamically added IP blacklist entries to 10 minutes.

<Sysname> system-view

[Sysname] attack-defense policy atk-policy-1

[Sysname-attack-defense-policy-atk-policy-1] scan detect level low action logging block-source timeout 10

signature { large-icmp | large-icmpv6 } max-length

Use signature { large-icmp | large-icmpv6 } max-length to set the maximum length of safe ICMP or ICMPv6 packets. A large ICMP or ICMPv6 attack occurs if an ICMP or ICMPv6 packet larger than the specified length is detected.

Use undo signature { large-icmp | large-icmpv6 } max-length to restore the default.

Syntax

signature { large-icmp | large-icmpv6 } max-length length

undo signature { large-icmp | large-icmpv6 } max-length

Default

The maximum length of safe ICMP or ICMPv6 packets is 4000 bytes.

Views

Attack defense policy view

Predefined user roles

network-admin

mdc-admin

Parameters

large-icmp: Specifies large ICMP packet attack signature.

large-icmpv6: Specifies large ICMPv6 packet attack signature.

length: Specifies the maximum length of safe ICMP or ICMPv6 packets, in bytes. The value range for ICMP packets is 28 to 65534. The value range for ICMPv6 packets is 48 to 65534.

Examples

# Set the maximum length of safe ICMP packets for large ICMP attack to 50000 bytes in attack defense policy atk-policy-1.

<Sysname> system-view

[Sysname] attack-defense policy atk-policy-1

[Sysname-attack-defense-policy-atk-policy-1] signature large-icmp max-length 50000

Related commands

signature detect

Use signature detect to enable signature detection for single-packet attacks and specify the prevention actions.

Use undo signature detect to disable signature detection for single-packet attacks.

Syntax

signature detect { fraggle | fragment | impossible | land | large-icmp | large-icmpv6 | smurf | snork | tcp-all-flags | tcp-fin-only | tcp-invalid-flags | tcp-null-flag | tcp-syn-fin | tiny-fragment | traceroute | udp-bomb | winnuke } [ action { { drop | logging } * | none } ]

undo signature detect { fraggle | fragment | impossible | land | large-icmp | large-icmpv6 | smurf | snork | tcp-all-flags | tcp-fin-only | tcp-invalid-flags | tcp-null-flag | tcp-syn-fin | tiny-fragment | traceroute | udp-bomb | winnuke }

signature detect { ip-option-abnormal | ping-of-death | teardrop } action { drop | logging } *

undo signature detect { ip-option-abnormal | ping-of-death | teardrop }

signature detect icmp-type { icmp-type-value | address-mask-reply | address-mask-request | destination-unreachable | echo-reply | echo-request | information-reply | information-request | parameter-problem | redirect | source-quench | time-exceeded | timestamp-reply | timestamp-request } [ action { { drop | logging } * | none } ]

undo signature detect icmp-type { icmp-type-value | address-mask-reply | address-mask-request | destination-unreachable | echo-reply | echo-request | information-reply | information-request | parameter-problem | redirect | source-quench | time-exceeded | timestamp-reply | timestamp-request }

signature detect icmpv6-type { icmpv6-type-value | destination-unreachable | echo-reply | echo-request | group-query | group-reduction | group-report | packet-too-big | parameter-problem | time-exceeded } [ action { { drop | logging } * | none } ]

undo signature detect icmpv6-type { icmpv6-type-value | destination-unreachable | echo-reply | echo-request | group-query | group-reduction | group-report | packet-too-big | parameter-problem | time-exceeded }

signature detect ip-option { option-code | internet-timestamp | loose-source-routing | record-route | route-alert | security | stream-id | strict-source-routing } [ action { { drop | logging } * | none } ]

undo signature detect ip-option { option-code | internet-timestamp | loose-source-routing | record-route | route-alert | security | stream-id | strict-source-routing }

signature detect ipv6-ext-header ext-header-value [ action { { drop | logging } * | none } ]

undo signature detect ipv6-ext-header next-header-value

Default

Signature detection is disabled for all single-packet attacks.

Views

Attack defense policy view

Predefined user roles

network-admin

mdc-admin

Parameters

fraggle: Specifies the fraggle attack.

fragment: Specifies the IP fragment attack.

icmp-type: Specifies an ICMP packet attack by the packet type. You can specify the packet type by a number or a keyword:

· icmp-type-value: Specifies the ICMP packet type in the range of 0 to 255.

· address-mask-reply: Specifies the ICMP address mask reply type.

· address-mask-request: Specifies the ICMP address mask request type.

· destination-unreachable: Specifies the ICMP destination unreachable type.

· echo-reply: Specifies the ICMP echo reply type.

· echo-request: Specifies the ICMP echo request type.

· information-reply: Specifies the ICMP information reply type.

· information-request: Specifies the ICMP information request type.

· parameter-problem: Specifies the ICMP parameter problem type.

· redirect: Specifies the ICMP redirect type.

· source-quench: Specifies the ICMP source quench type.

· time-exceeded: Specifies the ICMP time exceeded type.

· timestamp-reply: Specifies the ICMP timestamp reply type.

· timestamp-request: Specifies the ICMP timestamp request type.

icmpv6-type: Specifies an ICMPv6 packet attack by the packet type. You can specify the packet type by a number or a keyword:

· icmpv6-type-value: Specifies the ICMPv6 packet type in the range of 0 to 255.

· destination-unreachable: Specifies the ICMPv6 destination unreachable type.

· echo-reply: Specifies the ICMPv6 echo reply type.

· echo-request: Specifies the ICMPv6 echo request type.

· group-query: Specifies the ICMPv6 group query type.

· group-reduction: Specifies the ICMPv6 group reduction type.

· group-report: Specifies the ICMPv6 group report type.

· packet-too-big: Specifies the ICMPv6 packet too big type.

· parameter-problem: Specifies the ICMPv6 parameter problem type.

· time-exceeded: Specifies the ICMPv6 time exceeded type.

impossible: Specifies the IP impossible packet attack.

ip-option: Specifies an IP option. You can specify the IP option by a number or a keyword:

· option-code: Specifies the IP option in the range of 0 to 255.

· internet-timestamp: Specifies the timestamp option.

· loose-source-routing: Specifies the loose source routing option.

· record-route: Specifies the record route option.

· route-alert: Specifies the route alert option.

· security: Specifies the security option.

· stream-id: Specifies the stream identifier option.

· strict-source-routing: Specifies the strict source route option.

ip-option-abnormal: Specifies the abnormal IP option attack.

ipv6-ext-header ext-header-value: Specifies an IPv6 extension header by its value in the range of 0 to 255.

land: Specifies the Land attack.

large-icmp: Specifies the large ICMP packet attack.

large-icmpv6: Specifies the large ICMPv6 packet attack.

ping-of-death: Specifies the ping-of-death attack.

smurf: Specifies the smurf attack.

snork: Specifies the UDP snork attack.

tcp-all-flags: Specifies the attack where the TCP packet has all flags set.

tcp-fin-only: Specifies the attack where the TCP packet has only the FIN flag set.

tcp-invalid-flags: Specifies the attack that uses TCP packets with invalid flags.

tcp-null-flag: Specifies the attack where the TCP packet has no flags set.

tcp-syn-fin: Specifies the attack where the TCP packet has both SYN and FIN flags set.

teardrop: Specifies the teardrop attack.

tiny-fragment: Specifies the tiny fragment attack.

traceroute: Specifies the traceroute attack.

udp-bomb: Specifies the UDP bomb attack.

winnuke: Specifies the WinNuke attack.

action: Specifies the actions against the single-packet attack. If you do not specify this keyword, the default action of the attack level to which the single-packet attack belongs is used.

drop: Drops packets that match the specified signature.

logging: Enables logging for the specified single-packet attack.

none: Takes no action.

Usage guidelines

You can use this command multiple times to enable signature detection for multiple single-packet attack types.

When you specify a packet type by a number, if the packet type has a corresponding keyword, the keyword is displayed in command output. If the packet type does not have a corresponding keyword, the number is displayed.

Examples

# Enable signature detection for the IP fragment attack and specify the prevention action as drop in attack defense policy atk-policy-1.

<Sysname> system-view

[Sysname] attack-defense policy atk-policy-1

[Sysname-attack-defense-policy-atk-policy-1] signature detect fragment action drop

Related commands

signature level action

Use signature level action to specify the actions against single-packet attacks on a specific level.

Use undo signature level action to restore the default.

Syntax

signature level { high | info | low | medium } action { { drop | logging } * | none }

undo signature level { high | info | low | medium } action

Default

For informational-level and low-level single-packet attacks, the action is logging.

For medium-level and high-level single-packet attacks, the actions are logging and drop.

Views

Attack defense policy view

Predefined user roles

network-admin

mdc-admin

Parameters

high: Specifies the high level. None of the currently supported single-packet attacks belongs to this level.

info: Specifies the informational level. For example, large ICMP packet attack is on this level.

low: Specifies the low level. For example, the traceroute attack is on this level.

medium: Specifies the medium level. For example, the WinNuke attack is on this level.

drop: Drops packets that match the specified level.

logging: Enable logging for single-packet attacks on the specified level.

none: Takes no action.

Usage guidelines

If you enable signature detection for a single-packet attack also by using the signature detect command, action parameters in the signature detect command take effect.

Examples

# Specify the action against informational-level single-packet attacks as drop in attack defense policy atk-policy-1.

<Sysname> system-view

[Sysname] attack-defense policy 1

[Sysname-attack-defense-policy-1] signature level info action drop

Related commands

signature detect

signature level detect

Use signature level detect to enable signature detection for single-packet attacks on a specific level.

Use undo signature level detect to disable signature detection for single-packet attacks on a specific level.

Syntax

signature level { high | info | low | medium } detect

undo signature level { high | info | low | medium } detect

Default

Signature detection is disabled for all levels of single-packet attacks.

Views

Attack defense policy view

Predefined user roles

network-admin

mdc-admin

Parameters

high: Specifies the high level. None of the currently supported single-packet attacks belongs to this level.

info: Specifies the informational level. For example, large ICMP packet attack is on this level.

low: Specifies the low level. For example, the traceroute attack is on this level.

medium: Specifies the medium level. For example, the WinNuke attack is on this level.

Usage guidelines

According to their severity, single-packet attacks are divided into four levels: info, low, medium, and high. Enabling signature detection for a specific level enables signature detection for all single-packet attacks on that level. Use the signature level action command to specify the actions against single-packet attacks on a specific level. If you enable signature detection for a single-packet attack also by using the signature detect command, action parameters in the signature detect command take effect.

To display the level to which a single-packet attack belongs, use the display attack-defense policy command.

Examples

# Enable signature detection for informational-level single-packet attacks in attack defense policy atk-policy-1.

<Sysname> system-view

[Sysname] attack-defense policy 1

[Sysname-attack-defense-policy-1] signature level info detect

Related commands

display attack-defense policy

signature detect

signature level action

syn-ack-flood action

Use syn-ack-flood action to specify global actions against SYN-ACK flood attacks.

Use undo syn-ack-flood action to restore the default.

Syntax

syn-ack-flood action { drop | logging }*

undo syn-ack-flood action

Default

No global action is specified for SYN-ACK flood attacks.

Views

Attack defense policy view

Predefined user roles

network-admin

mdc-admin

Parameters

drop: Drops subsequent SYN-ACK packets destined for the victim IP addresses.

logging: Enables logging for SYN-ACK flood attack events.

Examples

# Specify drop as the global action against SYN-ACK flood attacks in attack defense policy atk-policy-1.

<Sysname> system-view

[Sysname] attack-defense policy atk-policy-1

[Sysname-attack-defense-policy-atk-policy-1] syn-ack-flood action drop

Related commands

syn-ack-flood detect

syn-ack-flood detect non-specific

syn-ack-flood threshold

syn-ack-flood detect

Use syn-ack-flood detect to configure IP address-specific SYN-ACK flood attack detection.

Use undo syn-ack-flood detect to remove the IP address-specific SYN-ACK flood attack detection configuration.

Syntax

syn-ack-flood detect { ip ipv4-address | ipv6 ipv6-address } [ vpn-instance vpn-instance-name ] [ threshold threshold-value ] [ action { { drop | logging } * | none } ]

undo syn-ack-flood detect { ip ipv4-address | ipv6 ipv6-address } [ vpn-instance vpn-instance-name ]

Default

IP address-specific SYN-ACK flood attack detection is not configured.

Views

Attack defense policy view

Predefined user roles

network-admin

mdc-admin

Parameters

ip ipv4-address: Specifies the IPv4 address to be protected. The ip-address argument cannot be all 1s or 0s.

ipv6 ipv6-address: Specifies the IPv6 address to be protected.

threshold threshold-value: Specifies the threshold for triggering SYN-ACK flood attack prevention. The value range is 1 to 1000000 in units of SYN-ACK packets sent to the specified IP address per second.

action: Specifies the actions when a SYN-ACK flood attack is detected. If no action is specified, the global actions set by the syn-ack-flood action command apply.

drop: Drops subsequent SYN-ACK packets destined for the protected IP address.

logging: Enables logging for SYN-ACK flood attack events.

none: Takes no action.

Usage guidelines

With SYN-ACK flood attack detection configured for an IP address, the device is in attack detection state. When the sending rate of SYN-ACK packets to the IP address reaches the threshold, the device enters prevention state and takes the specified actions. When the rate is below the silence threshold (three-fourths of the threshold), the device returns to the attack detection state.

You can configure SYN-ACK flood attack detection for multiple IP addresses in one attack defense policy.

Examples

# Configure SYN-ACK flood attack detection for 192.168.1.2 in attack defense policy atk-policy-1.

<Sysname> system-view

[Sysname] attack-defense policy atk-policy-1

[Sysname-attack-defense-policy-atk-policy-1] syn-ack-flood detect ip 192.168.1.2 threshold 2000

Related commands

syn-ack-flood action

syn-ack-flood detect non-specific

syn-ack-flood threshold

syn-ack-flood detect non-specific

Use syn-ack-flood detect non-specific to enable global SYN-ACK flood attack detection.

Use undo syn-ack-flood detect non-specific to disable global SYN-ACK flood attack detection.

Syntax

syn-ack-flood detect non-specific

undo syn-ack-flood detect non-specific

Default

Global SYN-ACK flood attack detection is disabled.

Views

Attack defense policy view

Predefined user roles

network-admin

mdc-admin

Usage guidelines

The global SYN-ACK flood attack detection applies to all IP addresses except for those specified by the syn-ack-flood detect command. The global detection uses the global trigger threshold set by the syn-ack-flood threshold command and global actions specified by the syn-ack-flood action command.

Examples

# Enable global SYN-ACK flood attack detection in attack defense policy atk-policy-1.

<Sysname> system-view

[Sysname] attack-defense policy atk-policy-1

[Sysname-attack-defense-policy-atk-policy-1] syn-ack-flood detect non-specific

Related commands

syn-ack-flood action

syn-ack-flood detect

syn-ack-flood threshold

Use syn-ack-flood threshold to set the global threshold for triggering SYN-ACK flood attack prevention.

Use undo syn-ack-flood threshold to restore the default.

Syntax

syn-ack-flood threshold threshold-value

undo syn-ack-flood threshold

Default

The global threshold is 1000 for triggering SYN-ACK flood attack prevention.

Views

Attack defense policy view

Predefined user roles

network-admin

mdc-admin

Parameters

threshold-value: Specifies the threshold value. The value range is 1 to 1000000 in units of SYN-ACK packets sent to an IP address per second.

Usage guidelines

With global SYN-ACK flood attack detection configured, the device is in attack detection state. When the sending rate of SYN-ACK packets to an IP address reaches the threshold, the device enters prevention state and takes the specified actions. When the rate is below the silence threshold (three-fourths of the threshold), the device returns to the attack detection state.

The global threshold applies to global SYN-ACK flood attack detection. Adjust the threshold according to the application scenarios. If the number of SYN-ACK packets sent to a protected server, such as an HTTP or FTP server, is normally large, set a large threshold. A small threshold might affect the server services. For a network that is unstable or susceptible to attacks, set a small threshold.

Examples

# Set the global threshold to 100 for triggering SYN-ACK flood attack prevention in attack defense policy atk-policy-1.

<Sysname> system-view

[Sysname] attack-defense policy atk-policy-1

[Sysname-attack-defense-policy-atk-policy-1] syn-ack-flood threshold 100

Related commands

syn-ack-flood action

syn-ack-flood detect

syn-ack-flood detect non-specific

syn-flood action

Use syn-flood action to specify global actions against SYN flood attacks.

Use undo syn-flood action to restore the default.

Syntax

syn-flood action { drop | logging } *

undo syn-flood action

Default

No global action is specified for SYN flood attacks.

Views

Attack defense policy view

Predefined user roles

network-admin

mdc-admin

Parameters

drop: Drops subsequent SYN packets destined for the victim IP addresses.

logging: Enables logging for SYN flood attack events.

Examples

# Specify drop as the global action against SYN flood attacks in attack defense policy atk-policy-1.

<Sysname> system-view

[Sysname] attack-defense policy atk-policy-1

[Sysname-attack-defense-policy-atk-policy-1] syn-flood action drop

Related commands

syn-flood detect

syn-flood detect non-specific

syn-flood threshold

syn-flood detect

Use syn-flood detect to configure IP address-specific SYN flood attack detection.

Use undo syn-flood detect to remove the IP address-specific SYN flood attack detection configuration.

Syntax

syn-flood detect { ip ipv4-address | ipv6 ipv6-address } [ vpn-instance vpn-instance-name ] [ threshold threshold-value ] [ action { { drop | logging } * | none } ]

undo syn-flood detect { ip ipv4-address | ipv6 ipv6-address } [ vpn-instance vpn-instance-name ]

Default

IP address-specific SYN flood attack detection is not configured.

Views

Attack defense policy view

Predefined user roles

network-admin

mdc-admin

Parameters

ip ipv4-address: Specifies the IPv4 address to be protected. The ip-address argument cannot be all 1s or 0s.

ipv6 ipv6-address: Specifies the IPv6 address to be protected.

threshold threshold-value: Specifies the threshold for triggering SYN flood attack prevention. The value range is 1 to 1000000 in units of SYN packets sent to the specified IP address per second.

action: Specifies the actions when a SYN flood attack is detected. If no action is specified, the global actions set by the syn-flood action command apply.

drop: Drops subsequent SYN packets destined for the protected IP address.

logging: Enables logging for SYN flood attack events.

none: Takes no action.

Usage guidelines

With SYN flood attack detection configured for an IP address, the device is in attack detection state. When the sending rate of SYN packets to the IP address reaches the threshold, the device enters prevention state and takes the specified actions. When the rate is below the silence threshold (three-fourths of the threshold), the device returns to the attack detection state.

You can configure SYN flood attack detection for multiple IP addresses in one attack defense policy.

Examples

# Configure SYN flood attack detection for 192.168.1.2 in attack defense policy atk-policy-1.

<Sysname> system-view

[Sysname] attack-defense policy atk-policy-1

[Sysname-attack-defense-policy-atk-policy-1] syn-flood detect ip 192.168.1.2 threshold 2000

Related commands

syn-flood action

syn-flood detect non-specific

syn-flood threshold

syn-flood detect non-specific

Use syn-flood detect non-specific to enable global SYN flood attack detection.

Use undo syn-flood detect non-specific to disable global SYN flood attack detection.

Syntax

syn-flood detect non-specific

undo syn-flood detect non-specific

Default

Global SYN flood attack detection is disabled.

Views

Attack defense policy view

Predefined user roles

network-admin

mdc-admin

Usage guidelines

The global SYN flood attack detection applies to all IP addresses except for those specified by the syn-flood detect command. The global detection uses the global trigger threshold set by the syn-flood threshold command and global actions specified by the syn-flood action command.

Examples

# Enable global SYN flood attack detection in attack defense policy atk-policy-1.

<Sysname> system-view

[Sysname] attack-defense policy atk-policy-1

[Sysname-attack-defense-policy-atk-policy-1] syn-flood detect non-specific

Related commands

syn-flood action

syn-flood detect

syn-flood threshold

Use syn-flood threshold to set the global threshold for triggering SYN flood attack prevention.

Use undo syn-flood threshold to restore the default.

Syntax

syn-flood threshold threshold-value

undo syn-flood threshold

Default

The global threshold is 1000 for triggering SYN flood attack prevention.

Views

Attack defense policy view

Predefined user roles

network-admin

mdc-admin

Parameters

threshold-value: Specifies the threshold value. The value range is 1 to 1000000 in units of SYN packets sent to an IP address per second.

Usage guidelines

With global SYN flood attack detection configured, the device is in attack detection state. When the sending rate of SYN packets to an IP address reaches the threshold, the device enters prevention state and takes the specified actions. When the rate is below the silence threshold (three-fourths of the threshold), the device returns to the attack detection state.

The global threshold applies to global SYN flood attack detection. Adjust the threshold according to the application scenarios. If the number of SYN packets sent to a protected server, such as an HTTP or FTP server, is normally large, set a large threshold. A small threshold might affect the server services. For a network that is unstable or susceptible to attacks, set a small threshold.

Examples

# Set the global threshold to 100 for triggering SYN flood attack prevention in attack defense policy atk-policy-1.

<Sysname> system-view

[Sysname] attack-defense policy atk-policy-1

[Sysname-attack-defense-policy-atk-policy-1] syn-flood threshold 100

Related commands

syn-flood action

syn-flood detect

syn-flood detect non-specific

udp-flood action

Use udp-flood action to specify global actions against UDP flood attacks.

Use undo udp-flood action to restore the default.

Syntax

udp-flood action { drop | logging } *

undo udp-flood action

Default

No global action is specified for UDP flood attacks.

Views

Attack defense policy view

Predefined user roles

network-admin

mdc-admin

Parameters

drop: Drops subsequent UDP packets destined for the victim IP addresses.

logging: Enables logging for UDP flood attack events.

Examples

# Specify drop as the global action against UDP flood attacks in attack defense policy atk-policy-1.

<Sysname> system-view

[Sysname] attack-defense policy atk-policy-1

[Sysname-attack-defense-policy-atk-policy-1] udp-flood action drop

Related commands

udp-flood detect

udp-flood detect non-specific

udp-flood threshold

udp-flood detect

Use udp-flood detect to configure IP address-specific UDP flood attack detection.

Use undo udp-flood detect to remove the IP address-specific UDP flood attack detection configuration.

Syntax

udp-flood detect { ip ipv4-address | ipv6 ipv6-address } [ vpn-instance vpn-instance-name ] [ threshold threshold-value ] [ action { { drop | logging } * | none } ]

undo udp-flood detect { ip ipv4-address | ipv6 ipv6-address } [ vpn-instance vpn-instance-name ]

Default

IP address-specific UDP flood attack detection is not configured.

Views

Attack defense policy view

Predefined user roles

network-admin

mdc-admin

Parameters

ip ipv4-address: Specifies the IPv4 address to be protected. The ip-address argument cannot be all 1s or 0s.

ipv6 ipv6-address: Specifies the IPv6 address to be protected.

threshold threshold-value: Specifies the threshold for triggering UDP flood attack prevention. The value range is 1 to 1000000 in units of UDP packets sent to the specified IP address per second.

action: Specifies the actions when a UDP flood attack is detected. If no action is specified, the global actions set by the udp-flood action command apply.

drop: Drops subsequent UDP packets destined for the protected IP address.

logging: Enables logging for UDP flood attack events.

none: Takes no action.

Usage guidelines

With UDP flood attack detection configured for an IP address, the device is in attack detection state. When the sending rate of UDP packets to the IP address reaches the threshold, the device enters prevention state and takes the specified actions. When the rate is below the silence threshold (three-fourths of the threshold), the device returns to the attack detection state.

You can configure UDP flood attack detection for multiple IP addresses in one attack defense policy.

Examples

# Configure UDP flood attack detection for 192.168.1.2 in attack defense policy atk-policy-1.

<Sysname> system-view

[Sysname] attack-defense policy atk-policy-1

[Sysname-attack-defense-policy-atk-policy-1] udp-flood detect ip 192.168.1.2 threshold 2000

Related commands

udp-flood action

udp-flood detect non-specific

udp-flood threshold

udp-flood detect non-specific

Use udp-flood detect non-specific to enable global UDP flood attack detection.

Use undo udp-flood detect non-specific to disable global UDP flood attack detection.

Syntax

udp-flood detect non-specific

undo udp-flood detect non-specific

Default

Global UDP flood attack detection is disabled.

Views

Attack defense policy view

Predefined user roles

network-admin

mdc-admin

Usage guidelines

The global UDP flood attack detection applies to all IP addresses except for those specified by the udp-flood detect command. The global detection uses the global trigger threshold set by the udp-flood threshold command and global actions specified by the udp-flood action command.

Examples

# Enable global UDP flood attack detection in attack defense policy atk-policy-1.

<Sysname> system-view

[Sysname] attack-defense policy atk-policy-1

[Sysname-attack-defense-policy-atk-policy-1] udp-flood detect non-specific

Related commands

udp-flood action

udp-flood detect

udp-flood threshold

Use udp-flood threshold to set the global threshold for triggering UDP flood attack prevention.

Use undo udp-flood threshold to restore the default.

Syntax

udp-flood threshold threshold-value

undo udp-flood threshold

Default

The global threshold is 1000 for triggering UDP flood attack prevention.

Views

Attack defense policy view

Predefined user roles

network-admin

mdc-admin

Parameters

threshold-value: Specifies the threshold value. The value range is 1 to 1000000 in units of UDP packets sent to an IP address per second.

Usage guidelines

With global UDP flood attack detection configured, the device is in attack detection state. When the sending rate of UDP packets to an IP address reaches the threshold, the device enters prevention state and takes the specified actions. When the rate is below the silence threshold (three-fourths of the threshold), the device returns to the attack detection state.

The global threshold applies to global UDP flood attack detection. Adjust the threshold according to the application scenarios. If the number of UDP packets sent to a protected server, such as an HTTP or FTP server, is normally large, set a large threshold. A small threshold might affect the server services. For a network that is unstable or susceptible to attacks, set a small threshold.

Examples

# Set the global threshold to 100 for triggering UDP flood attack prevention in attack defense policy atk-policy-1.

<Sysname> system-view

[Sysname] attack-defense policy atk-policy-1

[Sysname-attack-defense-policy-atk-policy-1] rst-flood threshold 100

Related commands

udp-flood action

udp-flood detect

udp-flood detect non-specific

09-Security Command Reference

Attack detection and prevention commands

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