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| Title | Size | Download |
|---|---|---|
| 04-BFD commands | 165.00 KB |
bfd detect-interface source-ip
bfd multi-hop destination-port
bfd multi-hop detect-multiplier
bfd multi-hop min-echo-receive-interval
bfd multi-hop min-receive-interval
bfd multi-hop min-transmit-interval
BFD commands
bfd dampening
Use bfd dampening to configure BFD session flapping suppression.
Use undo bfd dampening to disable BFD session flapping suppression.
Syntax
bfd dampening [ maximum maximum-interval initial initial-interval secondary secondary-interval ]
undo bfd dampening
Default
BFD sessions are not suppressed.
Views
System view
Predefined user roles
network-admin
Parameters
maximum-interval: Specifies the maximum time a BFD session is suppressed, in the range of 1 to 3600 seconds. The default is 20 seconds.
initial-interval: Specifies the amount of time a BFD session is suppressed for the first time. The value range for the initial-interval argument is 1 to 3600 seconds. The default is 6 seconds.
secondary-interval: Specifies the amount of time a BFD session is suppressed for the second time. The value range for the secondary-interval argument is 1 to 3600 seconds. The default is 10 seconds.
Usage guidelines
When BFD detects a link failure, it tears down the BFD session and notifies the upper-layer protocol of the failure. When the upper-layer protocol re-establishes a neighbor relationship, the BFD session comes up again. BFD session flaps occur when a link fails and recovers repeatedly, which consumes significant system resources and causes network instability.
This command allows you to suppress BFD session flapping by using the initial-interval, secondary-interval, and maximum-interval arguments.
· A BFD session is suppressed within the specified interval. The suppression time does not exceed the maximum-interval.
· After a BFD session goes down for the second time, it cannot be re-established within the initial-interval.
· After a BFD session goes down for the third time, it cannot be re-established within the secondary-interval.
· After a BFD session goes down for the fourth time and at any later time, the following rules apply:
¡ If secondary-interval × 2n-3 is smaller than or equal to the maximum-interval, the BFD session cannot be re-established within the secondary-interval × 2n-3.
¡ If secondary-interval × 2n-3 is greater than the maximum-interval, the BFD session cannot be re-established within the maximum-interval.
The letter n, starting from 4, is the number of times the BFD session flaps.
Examples
# Enable BFD session flapping suppression, and set the maximum-interval, initial-interval, and secondary-interval to 12 seconds, 4 seconds, and 8 seconds, respectively.
<Sysname> system-view
[Sysname] bfd dampening maximum 12 initial 4 secondary 8
bfd demand enable
Use bfd demand enable to enable the Demand BFD session mode.
Use undo bfd demand enable to restore the default.
Syntax
bfd demand enable
undo bfd demand enable
Default
The BFD session is in Asynchronous mode.
Views
Interface view
Predefined user roles
network-admin
Usage guidelines
In Demand mode, the device periodically sends BFD control packets. If the peer end is operating in Asynchronous mode (default), the peer end stops sending BFD control packets. If the peer end is operating in Demand mode, both ends stop sending BFD control packets. When a system in Demand mode wants to verify the connectivity to another system, it sends several BFD control packets with the Poll (P) bit set at the negotiated transmit interval. If no response is received within the detection interval, the session is considered down. If the connectivity is found to be up, no more BFD control packets are sent until the next command is issued. As a best practice, configure the bfd echo enable command together with this command to detect connectivity by sending Echo packets. If the device does not receive any Echo packets from the peer end, it considers the session down.
In Asynchronous mode, the device periodically sends BFD control packets. The device considers that the session is down if it does not receive any BFD control packets within a specific interval.
BFD version 0 does not support this command. The configuration does not take effect.
Examples
# Enable the Demand BFD session mode on VLAN-interface 11.
<Sysname> system-view
[Sysname] interface vlan-interface 11
[Sysname-Vlan-interface11] bfd demand enable
Related commands
bfd echo enable
bfd detect-interface source-ip
Use bfd detect-interface source-ip to associate the interface state with BFD.
Use undo bfd detect-interface to remove the association between the interface state and BFD.
Syntax
bfd detect-interface source-ip ip-address [ discriminator local local-value remote remote-value ]
undo bfd detect-interface
Default
The interface state is not associated with BFD.
Views
Interface view
Predefined user roles
network-admin
Parameters
ip-address: Specifies the source IP address for BFD control packets.
discriminator: Specifies BFD session discriminators. If you do not specify discriminators, the device obtains BFD session discriminators through autonegotiation.
local local-value: Specifies the local discriminator. The value range for the local-value argument is 3001 to 4000.
remote remote-value: Specifies the remote discriminator in the range of 1 to 4294967295.
Usage guidelines
By creating a BFD session for single-hop detection through exchange of BFD control packets, this feature implements fast link detection.. When BFD detects a link fault, it sets the link layer protocol state to DOWN(BFD). This behavior helps applications relying on the link layer protocol state achieve fast convergence. The source IP address of control packets is specified manually, and the destination IP address is fixed at 224.0.0.184. As a best practice, specify the IP address of the interface as the source IP address. If the interface does not have an IP address, specify a unicast IP address other than 0.0.0.0 as the source IP address.
You can associate the state of the following interfaces with BFD:
· Layer 2 Ethernet interfaces.
· Member ports in a Layer 2 aggregation group.
· Layer 3 Ethernet interfaces.
· Member ports in a Layer 3 aggregation group.
· VLAN interfaces.
This command must be configured on both ends of the link for a BFD session to be established.
For BFD detection to take effect, do not configure this command on both a Layer 2 Ethernet interface and the VLAN interface created for the VLAN to which the Layer 2 Ethernet interface is assigned.
If the peer device does not support obtaining BFD session discriminators through autonegotiation, you must specify the discriminators on both the local and peer devices. Without the discriminators, the BFD session cannot come up.
The BFD session discriminators must match on the local and peer devices. For example, if you configure bfd detect-interface source-ip 20.1.1.1 discriminator local 3002 remote 3100 on the local device, you must configure bfd detect-interface source-ip 20.1.1.1 discriminator local 3100 remote 3002 on the peer device.
The local discriminators of BFD sessions for interfaces on the same device must be different.
The echo function does not take effect on BFD sessions associated with interface states.
Examples
# Associate VLAN-interface 10 with BFD to detect the interface state, and specify the source IP address for BFD control packets as 20.1.1.1.
<Sysname> system-view
[Sysname] interface vlan-interface 10
[Sysname-Vlan-interface10] bfd detect-interface source-ip 20.1.1.1
bfd detect-multiplier
Use bfd detect-multiplier to set the single-hop detection time multiplier for control mode and echo mode.
Use undo bfd detect-multiplier to restore the default.
Syntax
bfd detect-multiplier value
undo bfd detect-multiplier
Default
The single-hop detection time multiplier is 5.
Views
Interface view
BFD template view
Static BFD session view
Predefined user roles
network-admin
Parameters
value: Specifies a detection time multiplier. The value range for this argument is 3 to 50.
Usage guidelines
The detection time multiplier determines the maximum number of concurrent BFD packets (including control packets and echo packets) that can be discarded.
Table 1 Actual detection interval calculation method
|
Mode |
Actual detection interval of the sender |
|
Echo mode |
Detection time multiplier of the sender × actual packet sending interval of the sender |
|
Control-mode BFD session in asynchronous mode |
Detection time multiplier of the receiver × MAX (minimum receiving interval supported by the sender, minimum sending interval supported by the receiver) |
|
Control-mode BFD session in demand mode |
Detection time multiplier of the sender × MAX (minimum sending interval supported by the sender, minimum receiving interval supported by the receiver) |
Only the following static BFD sessions support this command:
· Static BFD sessions in IPv4 control packet mode used for single-hop detection.
· Static BFD sessions in IPv4 echo packet mode used for single-hop detection.
· Static BFD sessions in IPv6 control packet mode used for single-hop detection.
· Static BFD sessions in IPv6 echo packet mode used for single-hop detection.
Examples
# Set the single-hop detection time multiplier for control mode and echo mode to 6 on VLAN-interface 11.
<Sysname> system-view
[Sysname] interface vlan-interface 11
[Sysname-Vlan-interface11] bfd detect-multiplier 6
bfd echo enable
Use bfd echo enable to enable the echo function.
Use undo bfd echo enable to disable the echo function.
Syntax
bfd echo [ receive | send ] enable
undo bfd echo [ receive | send ] enable
Default
The echo function is disabled.
Views
Interface view
Static BFD session view
Predefined user roles
network-admin
Parameters
receive: Specifies the echo packet receiving capability.
send: Specifies the echo packet sending capability.
Usage guidelines
If you enable the echo function for a BFD session in which control packets are sent and the session comes up, BFD performs the following operations:
· Periodically sends echo packets to detect link connectivity.
· Decreases the control packet receiving rate at the same time.
To enable only the echo packet receiving capability, use the bfd echo receive enable command.
To enable only the echo packet sending capability, use the bfd echo send enable command.
If you do not specify the receive or send keyword, the command enables both the echo packet receiving and sending capabilities.
The echo function does not take effect on BFD sessions associated with interface states.
The echo function does not take effect on BFD sessions in control packet mode that use IPv6 link-local addresses.
If you configure both the bfd detect-interface and bfd echo enable commands for an interface, only the bfd detect-interface command takes effect.
BFD version 0 does not support this command. The configuration does not take effect.
Only static BFD sessions in IPv4 or IPv6 control packet mode used for single-hop detection support this command.
Examples
# Enable the echo function on VLAN-interface 11.
<Sysname> system-view
[Sysname] interface vlan-interface 11
[Sysname-Vlan-interface11] bfd echo enable
bfd echo-source-ip
Use bfd echo-source-ip to configure the source IP address of BFD echo packets.
Use undo bfd echo-source-ip to remove the configured source IP address of BFD echo packets.
Syntax
bfd echo-source-ip ip-address
undo bfd echo-source-ip
Default
No source IP address is configured for BFD echo packets.
Views
System view
Predefined user roles
network-admin
Parameters
ip-address: Specifies the source IP address of BFD echo packets. The source IP address must be a valid unicast IPv4 address in dotted decimal notation.
Usage guidelines
As a best practice, execute this command only one end, and do not configure the source IP address to be on the same network segment as any local interface's IP address. If you configure such a source IP address, a large number of ICMP redirect packets might be sent from the peer, resulting in link congestion.
Examples
# Configure the source IP address of BFD echo packets as 8.8.8.8.
<Sysname> system-view
[Sysname] bfd echo-source-ip 8.8.8.8
bfd echo-source-ipv6
Use bfd echo-source-ipv6 to configure the source IPv6 address of BFD echo packets.
Use undo bfd echo-source-ipv6 to remove the configured source IPv6 address of BFD echo packets.
Syntax
bfd echo-source-ipv6 ipv6-address
undo bfd echo-source-ipv6
Default
No source IPv6 address is configured for BFD echo packets.
Views
System view
Predefined user roles
network-admin
Parameters
ipv6-address: Specifies the source IPv6 address for BFD echo packets.
Usage guidelines
The source IPv6 address of echo packets can only be a global unicast address.
As a best practice, execute this command only one end. The source IPv6 address cannot be on the same network segment as any local interface's IP address. Otherwise, a large number of ICMP redirect packets might be sent from the peer, resulting in link congestion.
Examples
# Configure the source IPv6 address of BFD echo packets as 80::2.
<Sysname> system-view
[Sysname] bfd echo-source-ipv6 80::2
bfd min-echo-receive-interval
Use bfd min-echo-receive-interval to set the minimum interval for receiving BFD echo packets.
Use undo bfd min-echo-receive-interval to restore the default.
Syntax
bfd min-echo-receive-interval interval
undo bfd min-echo-receive-interval
Default
The minimum interval for receiving BFD echo packets is 400 milliseconds.
Views
Interface view
BFD template view
Static BFD session view
Predefined user roles
network-admin
Parameters
interval: Specifies the minimum interval for receiving BFD echo packets, in milliseconds. The value takes 0 or is in the range of 3 to 10000.
Usage guidelines
This command sets the BFD echo packet receiving interval, which is the actual BFD echo packet sending interval.
The local end stops sending echo packets after autonegotiation with the remote end if the following conditions are met:
· The echo mode is enabled on the local end.
· The minimum interval for receiving BFD echo packets is set to 0 milliseconds on the remote end.
Only the following static BFD sessions support this command:
· Static BFD sessions in IPv4 control packet mode used for single-hop detection.
· Static BFD sessions in IPv4 echo packet mode used for single-hop detection.
· Static BFD sessions in IPv6 control packet mode used for single-hop detection.
· Static BFD sessions in IPv6 echo packet mode used for single-hop detection.
Examples
# Set the minimum interval for receiving BFD echo packets to 500 milliseconds on VLAN-interface 11.
<Sysname> system-view
[Sysname] interface vlan-interface 11
[Sysname-Vlan-interface11] bfd min-echo-receive-interval 500
bfd min-receive-interval
Use bfd min-receive-interval to set the minimum interval for receiving single-hop BFD control packets.
Use undo bfd min-receive-interval to restore the default.
Syntax
bfd min-receive-interval interval
undo bfd min-receive-interval
Default
The minimum interval for receiving single-hop BFD control packets is 400 milliseconds.
Views
Interface view
BFD template view
Static BFD session view
Predefined user roles
network-admin
Parameters
interval: Specifies the minimum interval for receiving single-hop BFD control packets, in milliseconds. The value range for this argument is 3 to 1000.
Usage guidelines
Use this command to prevent the control packet sending rate of the peer end from exceeding the control packet receiving rate of the local end.
The actual control packet sending interval of the peer end takes the greater value between the following values:
· Minimum interval for transmitting BFD control packets on the peer end.
· Minimum interval for receiving BFD control packets on the local end.
Only static BFD sessions in IPv4 or IPv6 control packet mode used for single-hop detection support this command.
Examples
# Set the minimum interval for receiving single-hop BFD control packets to 500 milliseconds on VLAN-interface 11.
<Sysname> system-view
[Sysname] interface vlan-interface 11
[Sysname-Vlan-interface11] bfd min-receive-interval 500
bfd min-transmit-interval
Use bfd min-transmit-interval to set the minimum interval for transmitting single-hop BFD control packets.
Use undo bfd min-transmit-interval to restore the default.
Syntax
bfd min-transmit-interval interval
undo bfd min-transmit-interval
Default
The minimum interval for transmitting single-hop BFD control packets is 400 milliseconds.
Views
Interface view
BFD template view
Static BFD session view
Predefined user roles
network-admin
Parameters
interval: Specifies the minimum interval for transmitting single-hop BFD control packets, in milliseconds. The value range for this argument is 3 to 1000.
Usage guidelines
Use this command to prevent the BFD packet sending rate from exceeding the device capability.
The actual BFD control packet transmitting interval on the local end is the greater value between the following values:
· Minimum interval for transmitting BFD control packets on the local end.
· Minimum interval for receiving BFD control packets on the peer end.
Only static BFD sessions in IPv4 or IPv6 control packet mode used for single-hop detection support this command.
Examples
# Set the minimum interval for transmitting single-hop BFD control packets to 500 milliseconds on VLAN-interface 11.
<Sysname> system-view
[Sysname] interface vlan-interface 11
[Sysname-Vlan-interface11] bfd min-transmit-interval 500
bfd multi-hop destination-port
Use bfd multi-hop destination-port to configure the destination port number for multihop BFD control packets.
Use undo bfd multi-hop destination-port to restore the default.
Syntax
bfd multi-hop destination-port port-number
undo bfd multi-hop destination-port
Default
The destination port number for multihop BFD control packets is 4784.
Views
System view
Predefined user roles
network-admin
Parameters
port-number: Specifies the destination port number of multihop BFD control packets, 3784 or 4784.
Usage guidelines
IANA assigned port number 4784 to BFD for multihop BFD detection in control packet mode. By default, H3C devices use 4784 as the destination port number for multihop BFD control packets, while devices from other vendors might use 3784. To avoid BFD session establishment failures, make sure the devices on both ends of the BFD session use the same destination port number for multihop BFD control packets.
This command applies to only new multihop BFD sessions in control packet mode.
Examples
# Specify the destination port number for multihop BFD control packets as 3784.
<Sysname> system-view
[Sysname] bfd multi-hop destination-port 3784
bfd multi-hop detect-multiplier
Use bfd multi-hop detect-multiplier to set the multihop detection time multiplier for control mode or echo mode.
Use undo bfd multi-hop detect-multiplier to restore the default.
Syntax
bfd multi-hop detect-multiplier value
undo bfd multi-hop detect-multiplier
Default
The multihop detection time multiplier for control mode is 5.
Views
System view
Static BFD session view
Predefined user roles
network-admin
Parameters
value: Specifies the multihop detection time multiplier. The value range for this argument is 3 to 50.
Usage guidelines
The detection time multiplier determines the maximum number of concurrent BFD control packets that can be discarded.
Table 2 Actual detection interval calculation method
|
Mode |
Actual detection interval of the sender |
|
Control-mode BFD session in asynchronous mode |
Detection time multiplier of the receiver × MAX (minimum receiving interval supported by the sender, minimum sending interval supported by the receiver) |
|
Control-mode BFD session in demand mode |
Detection time multiplier of the sender × MAX (minimum sending interval supported by the sender, minimum receiving interval supported by the receiver) |
Only the following static BFD sessions support this command:
· Static BFD sessions in IPv4 control packet mode used for multihop detection.
· Static BFD sessions in IPv4 echo packet mode used for multihop detection.
· Static BFD sessions in IPv6 control packet mode used for multihop detection.
· Static BFD sessions in IPv6 echo packet mode used for multihop detection.
Examples
# Set the multihop detection time multiplier to 6 for control mode.
<Sysname> system-view
[Sysname] bfd multi-hop detect-multiplier 6
bfd multi-hop min-echo-receive-interval
Use bfd multi-hop min-echo-receive-interval to set the minimum interval for receiving multihop BFD echo packets.
Use undo bfd multi-hop min-echo-receive-interval to restore the default.
Syntax
bfd multi-hop min-echo-receive-interval interval
undo bfd multi-hop min-echo-receive-interval
Default
The minimum interval for receiving multihop BFD echo packets is 400 milliseconds.
Views
System view
Static BFD session view
Predefined user roles
network-admin
Parameters
interval: Specifies the minimum interval for receiving multihop BFD echo packets, in milliseconds. The value for this argument takes 0 or is in the range of 3 to 1000.
Usage guidelines
The interval for receiving multihop BFD echo packets is also the interval for sending multihop BFD echo packets. By executing this command, you can control both the receiving interval and sending interval for multihop BFD echo packets.
Only static BFD sessions in IPv4 or IPv6 echo packet mode used for multihop detection support this command.
Examples
# Set the minimum interval for receiving multihop BFD echo packets to 500 milliseconds.
<Sysname> system-view
[Sysname] bfd multi-hop min-echo-receive-interval 500
Related commands
bfd static
bfd multi-hop min-receive-interval
Use bfd multi-hop min-receive-interval to set the minimum interval for receiving multihop BFD control packets.
Use undo bfd multi-hop min-receive-interval to restore the default.
Syntax
bfd multi-hop min-receive-interval interval
undo bfd multi-hop min-receive-interval
Default
The minimum interval for receiving multihop BFD control packets is 400 milliseconds.
Views
System view
Static BFD session view
Predefined user roles
network-admin
Parameters
interval: Specifies the minimum interval for receiving multihop BFD control packets, in milliseconds. The value range for this argument is 3 to 1000.
Usage guidelines
Use this command to prevent the packet sending rate of the peer end from exceeding the packet receiving capability (minimum control packet receiving interval) of the local end. If the receiving capability is exceeded, the peer end dynamically adjusts the BFD control packet sending interval to the minimum control packet receiving interval of the local end.
Only static BFD sessions in IPv4 or IPv6 control packet mode used for multihop detection support this command.
Examples
# Set the minimum interval for receiving multihop BFD control packets to 500 milliseconds.
<Sysname> system-view
[Sysname] bfd multi-hop min-receive-interval 500
bfd multi-hop min-transmit-interval
Use bfd multi-hop min-transmit-interval to set the minimum interval for transmitting multihop BFD control packets.
Use undo bfd multi-hop min-transmit-interval to restore the default.
Syntax
bfd multi-hop min-transmit-interval interval
undo bfd multi-hop min-transmit-interval
Default
The minimum interval for transmitting multihop BFD control packets is 400 milliseconds.
Views
System view
Static BFD session view
Predefined user roles
network-admin
Parameters
interval: Specifies the minimum interval for transmitting multihop BFD control packets, in milliseconds. The value range for this argument is 3 to 1000.
Usage guidelines
Use this command to prevent the BFD packet sending rate from exceeding the device capability.
The actual BFD control packet transmitting interval on the local end is the greater value between the following values:
· Minimum interval for transmitting BFD control packets on the local end.
· Minimum interval for receiving BFD control packets on the peer end.
Only static BFD sessions in IPv4 or IPv6 control packet mode used for multihop detection support this command.
Examples
# Set the minimum interval for transmitting multihop BFD control packets to 500 milliseconds.
<Sysname> system-view
[Sysname] bfd multi-hop min-transmit-interval 500
bfd session init-mode
Use bfd session init-mode to configure the mode for establishing a BFD session.
Use undo bfd session init-mode to restore the default.
Syntax
bfd session init-mode { active | passive }
undo bfd session init-mode
Default
BFD uses the active mode.
Views
System view
Predefined user roles
network-admin
Parameters
active: Specifies the active mode. In active mode, BFD actively transmits BFD control packets to the remote device, regardless of whether it receives a BFD control packet from the remote device.
passive: Specifies the passive mode. In passive mode, BFD does not actively transmit a BFD control packet to the remote end; it transmits a BFD control packet only after receiving a BFD control packet from the remote end.
Usage guidelines
A minimum of one end must operate in active mode for a BFD session to be established.
BFD version 0 does not support this command. The configuration does not take effect.
Examples
# Configure the session establishment mode as passive.
<Sysname> system-view
[Sysname] bfd session init-mode passive
bfd static
Use bfd static to create a static BFD session and enter its view, or enter the view of an existing static BFD session.
Use undo bfd static to delete a static BFD session and all its settings.
Syntax
Static BFD session for single-hop detection with IPv4 control packets:
bfd static session-name [ peer-ip ipv4-address interface interface-type interface-number source-ip ipv4-address ]
undo bfd static session-name
Static BFD session for multihop detection with IPv4 control packets:
bfd static session-name [ peer-ip ipv4-address [ vpn-instance vpn-instance-name ] source-ip ipv4-address [ track-interface interface-type interface-number ] ]
undo bfd static session-name
Static BFD session for single-hop detection with IPv4 echo packets:
bfd static session-name [ peer-ip ipv4-address interface interface-type interface-number destination-ip ipv4-address [ source-ip ipv4-address ] one-arm-echo [ discriminator auto ] ]
undo bfd static session-name
Static BFD session for multihop detection with IPv4 echo packets:
bfd static session-name [ peer-ip ipv4-address [ vpn-instance vpn-instance-name ] destination-ip ipv4-address [ source-ip ipv4-address ] one-arm-echo [ discriminator auto ] ]
undo bfd static session-name
Static BFD session for single-hop detection with IPv6 control packets:
bfd static session-name [ peer-ipv6 ipv6-address interface interface-type interface-number source-ipv6 ipv6-address ]
undo bfd static session-name
Static BFD session for multihop detection with IPv6 control packets:
bfd static session-name [ peer-ipv6 ipv6-address [ vpn-instance vpn-instance-name ] source-ipv6 ipv6-address [ track-interface interface-type interface-number ] ]
undo bfd static session-name
Static BFD session for single-hop detection with IPv6 echo packets:
bfd static session-name [ peer-ipv6 ipv6-address interface interface-type interface-number destination-ipv6 ipv6-address [ source-ipv6 ipv6-address ] one-arm-echo [ discriminator auto ] ]
undo bfd static session-name
Static BFD session for multihop detection with IPv6 echo packets:
bfd static session-name [ peer-ipv6 ipv6-address [ vpn-instance vpn-instance-name ] destination-ipv6 ipv6-address [ source-ipv6 ipv6-address ] one-arm-echo [ discriminator auto ] ]
undo bfd static session-name
Default
No static BFD sessions exist.
Views
System view
Predefined user roles
network-admin
Parameters
session-name: Specifies a static BFD session name, a case-sensitive string of 1 to 64 characters.
peer-ip ipv4-address: Specifies the peer IPv4 address in dotted decimal notation. It must be a valid unicast IPv4 address. For a static BFD session in control packet mode, the peer IPv4 address and the source IPv4 address determine the path to be detected. For a static BFD session in echo packet mode, the peer IPv4 address and the destination IPv4 address determine the path to be detected.
peer-ipv6 ipv6-address: Specifies the peer IPv6 address. For a static BFD session in control packet mode, the peer IPv6 address and the source IPv6 address determine the path to be detected. For a static BFD session in echo packet mode, the peer IPv6 address and the destination IPv6 address determine the path to be detected.
vpn-instance vpn-instance-name: Specifies an MPLS L3VPN instance by its name, a case-sensitive string of 1 to 31 characters. If you do not specify this option, the static BFD session belongs to the public network.
interface interface-type interface-number: Specifies an interface by its type and number. BFD uses the specified interface as the outgoing interface for outgoing packets.
destination-ip ipv4-address: Specifies the destination IPv4 address for echo packets, in dotted decimal notation. It must be a valid unicast IPv4 address of the local end.
destination-ipv6 ipv6-address: Specifies the destination IPv6 address for echo packets. It must be the IPv6 address of the local end.
source-ip ipv4-address: Specifies the source IPv4 address for BFD packets, in dotted decimal notation. It must be a valid unicast IPv4 address.
source-ipv6 ipv6-address: Specifies the source IPv6 address for BFD packets.
one-arm-echo: Specifies the static BFD session mode as echo packet mode.
discriminator: Specifies BFD session discriminators.
auto: Enables the device to automatically assign local discriminator values to static BFD sessions.
track-interface interface-type interface-number: Specifies an interface monitored by the static BFD session. When the monitored interface fails, the static BFD session changes to the down state. If you do not specify this option, the static BFD session does not monitor any interfaces.
Usage guidelines
A static BFD session can be used for single-hop detection and multihop detection. By working with Track, a static BFD session can provide fast failure detection. For more information about Track association with BFD, see Track in High Availability Configuration Guide.
If a static BFD session in control packet mode is created on the peer device, you must use this command to create a static BFD session on the local device. The BFD session discriminators must match on the local and peer devices. For example, if you execute the bfd static abc peer-ip 20.1.1.1 source-ip 20.1.1.2 command in system view and the discriminator local 513 and discriminator remote 514 commands in static BFD session on the local device, you must execute the bfd static abc peer-ip 20.1.1.2 source-ip 20.1.1.1 command and the discriminator local 514 and discriminator remote 513 commands on the peer device.
When creating a static BFD session, you must specify a peer IP address. The system checks only the format of the IP address but not its correctness. If the peer IPv4 or IPv6 address is incorrect, the static BFD session cannot be established. The bfd static session-name command without any parameters specified can only be used to enter the view of an existing static BFD session.
For a static BFD session in control packet mode, you must use the discriminator command to specify its local and remote discriminators. Otherwise, the static BFD session does not take effect.
You need to create a static BFD session on only the local device if you use the echo packet mode for detection. As a best practice, specify the source IP address for echo packets when creating a static BFD session. Make sure the specified source IP address does not belong to the subnet where a local interface resides. Without a source IP address specified, the device uses the IP address specified in the bfd echo-source-ip or bfd echo-source-ipv6 command as the source IP address of echo packets. If you do not specify the source IP address by using either method, the device uses the IP address specified in the destination-ip or destination-ipv6 command as the source IP address of echo packets.
To use a static BFD session in control packet mode for single-hop detection, you must perform the following configuration:
· Specify the IP address of the peer interface for the peer-ip/peer-ipv6 keyword.
· Specify the IP address of the local interface for the source-ip/source-ipv6 keyword.
For a static BFD session in control packet mode, the source IP address of BFD packets is the IP address specified for the source-ip/source-ipv6 keyword, and the destination IP address is the IP address specified for the peer-ip/peer-ipv6 keyword.
For a static BFD session in echo packet mode, the source IP address of BFD packets is the IP address specified for the source-ip/source-ipv6 keyword, and the destination IP address is the IP address specified for the destination-ip/destination-ipv6 keyword. If no source IP address is specified, the device uses the IP address specified in the destination-ip or destination-ipv6 command as the source IP address of echo packets.
To modify a static BFD session, delete the static BFD session and then configure a new static BFD session.
Different static BFD sessions cannot have the same local discriminator.
A static BFD session can monitor the following interfaces:
· Layer 2 Ethernet interfaces.
· Layer 3 Ethernet interfaces and their subinterfaces.
· Layer 2 aggregate interfaces and their member ports.
· Layer 3 aggregate interfaces and their subinterfaces and member ports.
Examples
# Create a static BFD session and enter its view. The static BFD session detects the path between 1.1.1.1 and 1.1.1.2 and uses VLAN-interface 10 to send BFD packets with source IP address 1.1.1.1 and destination IP address is 1.1.1.2. The local discriminator is 1537, and the remote discriminator is 2048.
<Sysname> system-view
[Sysname] bfd static abc peer-ip 1.1.1.2 interface vlan-interface 10 source-ip 1.1.1.1 discriminator local 1537 remote 2048
[Sysname-bfd-static-session-abc]
# Create a static BFD session in echo mode and enter its view. The static BFD session detects the path between 1.1.1.1 and 1.1.1.2 and uses VLAN-interface 11 to send BFD packets with source IP address 9.9.9.9 and destination IP address is 1.1.1.2.
<Sysname> system-view
[Sysname] bfd static abc peer-ip 1.1.1.1 interface vlan-interface 11 destination-ip 1.1.1.2 source-ip 9.9.9.9 one-arm-echo discriminator auto
[Sysname-bfd-static-session-abc]
Related commands
bfd echo-source-ip
bfd echo-source-ipv6
discriminator
bfd template
Use bfd template to create a BFD template and enter its view, or enter the view of an existing BFD template.
Use undo bfd template to delete the BFD template.
Syntax
bfd template template-name
undo bfd template template-name
Default
No BFD templates exist.
Views
System view
Predefined user roles
network-admin
Parameters
template-name: Specifies the template name, a case-sensitive string of 1 to 63 characters.
Examples
# Create BFD template bfd1 and enter BFD template view.
<Sysname> system-view
[Sysname] bfd template bfd1
[Sysname-bfd-template-bfd1]
discriminator
Use discriminator to specify the local and remote discriminators for a static BFD session.
Use undo discriminator to remove the local and remote discriminator for the static BFD session.
Syntax
discriminator { local local-value | remote remote-value }
undo discriminator { local local-value | remote remote-value }
Default
No local and remote discriminators are specified for a static BFD session.
Views
Static BFD session view
Predefined user roles
network-admin
Parameters
local local-value: Specifies the local discriminator in the range of 1 to 32768.
remote remote-value: Specifies the remote discriminator in the range of 1 to 4294967295.
Usage guidelines
Use this command only if you do not specify the local or remote discriminator when creating a static BFD session.
To modify the local or remote discriminator of a static BFD session, execute the undo discriminator and then the discriminator command to specify a new local or remote discriminator.
Different static BFD sessions cannot have the same local discriminator.
Examples
# Create local discriminator 1537 and remote discriminator 2048 for static BFD session abc.
<Sysname> system-view
[Sysname] bfd static abc
[Sysname-bfd-static-session-abc] discriminator local 1537
[Sysname-bfd-static-session-abc] discriminator remote 2048
Related commands
bfd static
display bfd session
Use display bfd session to display BFD session information.
Syntax
display bfd session [ discriminator local-value | discriminator local local-value | static session-name | verbose ]
display bfd session [ [ dynamic ] [ control | echo ] [ ip ] [ state { admin-down | down | init | up } ] [ discriminator remote remote-value ] [ peer-ip ipv4-address [ vpn-instance vpn-instance-name ] ] [ verbose ] ]
display bfd session [ [ dynamic ] [ control | echo ] [ ipv6 ] [ state { admin-down | down | init | up } ] [ discriminator remote remote-value ] [ peer-ipv6 ipv6-address [ vpn-instance vpn-instance-name ] ] [ verbose ] ]
display bfd session [ [ static ] [ ip ] [ state { admin-down | down | init | up } ] [ discriminator remote remote-value ] [ peer-ip ipv4-address [ vpn-instance vpn-instance-name ] ] [ verbose ]
display bfd session [ [ static ] [ ipv6 ] [ state { admin-down | down | init | up } ] [ discriminator remote remote-value ] [ peer-ipv6 ipv6-address [ vpn-instance vpn-instance-name ] ] [ verbose ]
Views
Any view
Predefined user roles
network-admin
network-operator
Parameters
discriminator local-value: Specifies a BFD session by its local discriminator in the range of 1 to 4294967295. If you do not specify a BFD session, this command displays information about all BFD sessions.
discriminator local local-value: Specifies a BFD session by its local discriminator in the range of 1 to 4294967295. If you do not specify a BFD session, this command displays information about all BFD sessions.
static session-name: Specifies a static BFD session by its name, a case-sensitive string of 1 to 64 characters.
dynamic: Specifies dynamic BFD sessions.
static: Specifies static BFD sessions.
control: Specifies BFD sessions in control packet mode.
echo: Specifies BFD sessions in echo mode.
ip: Specifies BFD sessions used to detect IPv4 links.
ipv6: Specifies BFD sessions used to detect IPv6 links.
state: Displays BFD sessions by session state.
down: Specifies BFD sessions in Down state.
admin-down: Specifies BFD sessions in AdminDown state.
init: Specifies BFD sessions in Init state.
up: Specifies BFD sessions in Up state.
discriminator remote remote-value: Specifies a BFD session by its remote discriminator in the range of 1 to 4294967295.
peer-ip ipv4-address: Specifies a BFD session by the peer IPv4 address in dotted decimal notation.
peer-ipv6 ipv6-address: Specifies a BFD session by the peer IPv6 address.
vpn-instance vpn-instance-name: Specifies an MPLS L3VPN instance by its name, a case-sensitive string of 1 to 31 characters. If you do not specify this option, the command displays the BFD sessions of the public network.
verbose: Displays detailed BFD session information. If you do not specify this keyword, the command displays brief BFD session information.
Usage guidelines
If you do not specify the dynamic or static keyword, this command displays all dynamic and static BFD sessions.
The discriminator local-value and discriminator local local-value parameters have the same effect. The only difference is that you do not need to enter local when using the latter.
Examples
# Display brief information about all IPv4 BFD sessions.
<Sysname> display bfd session
Total sessions: 3 Up sessions: 3 Init mode: Active
IPv4 session working in control mode:
LD/RD SourceAddr DestAddr State Holdtime Interface
513/513 1.1.1.1 1.1.1.2 Up 2297ms Vlan100
IPv6 session working in control mode:
Local discr: 513 Remote discr: 513
Source IP: FE80::20C:29FF:FED4:7171
Destination IP: FE80::20C:29FF:FE72:AC4D
Session state: Up Interface: Vlan100
Hold time: 2142ms
IPv4 static session working in echo packet mode:
LD SourceAddr DestAddr State Holdtime Interface
327 192.168.1.101 192.168.1.83 Up 2050ms Vlan100
Table 3 Command output
|
Field |
Description |
|
Total Session Num |
Total number of BFD sessions. |
|
Up Session Num |
Total number of active BFD sessions. |
|
Init Mode |
BFD operating mode: Active or passive. |
|
IPv4 session working in control mode |
BFD session type and operating mode: · IPv4 session working in control mode—IPv4 session in control mode. · IPv4 session working in echo mode. · IPv6 session working in control mode—IPv6 session in control mode. · IPv6 session working in echo mode. · IPv4 static session working in control packet mode. · IPv6 static session working in control packet mode. |
|
LD/RD |
Local discriminator/Remote discriminator of the session. |
|
SourceAddr |
Source IPv4 address of the session. |
|
DestAddr |
Destination IPv4 address of the session. |
|
State |
Session state: Down, Init, Adown, or Up. |
|
Holdtime |
Length of time before session detection timer expires. For a BFD session in Down state, this field displays 0ms. |
|
Interface |
Name of the interface of the session. |
|
Local discr |
Local discriminator of the session. |
|
Remote discr |
Remote discriminator of the session. |
|
Source IP |
Source IPv6 address of the session. |
|
Destination IP |
Destination IPv6 address of the session. |
|
Session state |
Session state: Down, Adown, Init, or Up. |
|
Hold time |
Length of time before session detection timer expires. For a BFD session in Down state, this field displays 0ms. |
# Display detailed BFD session information.
<Sysname> display bfd session verbose
Total Session Num: 4 Up Session Num: 4 Init Mode: Active
IPv4 session working in control mode:
Local Discr: 513 Remote Discr: 513
Source IP: 1.1.1.1 Destination IP: 1.1.1.2
Destination port: 3784 Session State: Up
Interface: Vlan-interface100
Min Tx Inter: 500ms Act Tx Inter: 500ms
Min Rx Inter: 500ms Detect Inter: 2500ms
Rx Count: 42 Tx Count: 43
Connect Type: Direct Running Up for: 00:00:20
Hold Time: 2078ms Auth mode: None
Detect Mode: Async Slot: 0
Protocol: OSPF
Version: 1
Diag Info: No Diagnostic
IPv6 session working in control mode:
Local discr: 513 Remote discr: 513
Source IP: FE80::20C:29FF:FED4:7171
Destination IP: FE80::20C:29FF:FE72:AC4D
Destination port: 3784 Session state: Up
Interface: Vlan-interface100
Min Tx interval: 500ms Actual Tx interval: 500ms
Min Rx interval: 500ms Detection time: 2500ms
Rx count: 38 Tx count: 38
Connection type: Direct Up duration: 00:00:15
Hold time: 2211ms Auth mode: None
Detection mode: Async Slot: 0
Protocol: OSPFv3
Version: 1
Diag info: No Diagnostic
IPv4 session working in control mode:
Session name: abc
Local discr: 310 Remote discr: 308
Source IP: 12.1.1.1 Destination IP: 12.1.1.2
Destination port: 3784 Session state: Up
Interface: Vlan-interface100
Min Tx interval: 500ms Actual Tx interval: 500ms
Min Rx interval: 500ms Detection time: 2500ms
Rx count: 514 Tx count: 514
Connection type: Direct Up duration: 00:00:15
Hold time: 2120ms Auth mode: None
Detection mode: Async Slot: 0
Protocol: STATIC_IPv4
Version: 1
Diag info: No Diagnostic
IPv6 session working in control mode:
Session name: bbbb
Local discr: 1700 Remote discr: 1700
Source IP: FE80::20C:29FF:FED4:7171
Destination IP: FE80::20C:29FF:FE72:AC4D
Destination port: 3784 Session state: Up
Interface: Vlan-interface100
Min Tx interval: 500ms Actual Tx interval: 500ms
Min Rx interval: 500ms Detection time: 2500ms
Rx count: 38 Tx count: 38
Connection type: Direct Up duration: 00:00:15
Hold time: 2211ms Auth mode: None
Detection mode: Async Slot: 0
Protocol: STATIC_IPv6
Version: 1
Diag info: No Diagnostic
Table 4 Command output
|
Field |
Description |
|
Total Session Num |
Total number of BFD sessions. |
|
Up Session Num |
Total number of active BFD sessions. |
|
Init Mode |
BFD operating mode: Active or passive. |
|
IPv4 session working in control mode |
BFD session type and operating mode: · IPv4 session working in control mode—IPv4 session in control mode. · IPv4 session working in echo mode. · IPv6 session working in control mode—IPv6 session in control mode. · IPv6 session working in echo mode. · IPv4 static session working in control packet mode. · IPv6 static session working in control packet mode. |
|
Session name |
Static BFD session name. This field appears only for a static BFD session. |
|
Local Discr |
Local discriminator of the session. |
|
Remote Discr |
Remote discriminator of the session. |
|
Source IP |
Source IP address of the session. |
|
Destination IP |
Destination IP address of the session. |
|
Destination port |
Destination port number in BFD packets defined in Comware: · The destination port number in single-hop BFD control packets is 3784. · The destination port number in single-hop or multihop BFD echo packets is 3785. · The destination port number in multihop BFD control packets is 4784. · The destination port number in BFD control packets for association between link aggregation and BFD is 6784. The device uses the destination port number in incoming packets that are not defined in Comware as the destination port number in outgoing BFD packets. |
|
Session State |
Session state: Down, Adown, Init, or Up. |
|
Interface |
Name of the interface of the session. |
|
Min Tx Inter |
Minimum transmit interval. |
|
Min Rx Inter |
Minimum receive interval. |
|
Act Tx Inter |
Actual transmit interval. |
|
Detect Inter |
Actual session detection timer. |
|
Rx Count |
Number of packets received. |
|
Tx Count |
Number of packets sent. |
|
Hold Time |
Length of time before session detection timer expires. |
|
Auth mode |
This field is not supported in the current software version. Session authentication mode. |
|
Connect Type |
Connection type of the interface: Direct or indirect. |
|
Running up for |
Time period for which the session has been up. |
|
Detect Mode |
Detection mode: · Async—Asynchronous mode. · Demand—Demand mode. · Async/Echo—Asynchronous mode with echo detection enabled. · Demand/Echo—Demand mode with echo detection enabled. |
|
Slot |
Slot number of the card where the BFD session resides. |
|
Protocol |
Protocol associated with BFD: · OSPF. · ISIS_BR_L1—IS-IS with the network type as broadcast and the router type as Level 1. · ISIS_BR_L2—IS-IS with the network type as broadcast and the router type as Level 2. · ISIS_P2P—IS-IS with the network type as P2P. · ISIS6_BR_L1—IPv6 IS-IS with the network type as broadcast and the router type as Level 1. · ISIS6_BR_L2—IPv6 IS-IS with the network type as broadcast and the router type as Level 2. · ISIS6_P2P—IPv6 IS-IS with the network type as P2P. · BGP. · STATIC4—IPv4 static routing. · TRACK—Track. · RIP. · IPFRR—FIB IP FRR. · MAD. · OSPFv3. · BGP4+. · STATIC6—IPv6 static routing. · RIPNG—RIPng. · Interface—Interface state. · LAGG—Link aggregation. · STATIC_IPv4—IPv4 static BFD session. · STATIC_IPv6—IPv6 static BFD session. |
|
Diag Info |
Diagnostic information about the session: · No Diagnostic. · Control Detection Time Expired—A control-mode BFD session goes down because local detection times out. · Echo Function Failed—An echo-mode BFD session goes down, because local detection times out or the source IP address of echo packets is deleted. · Neighbor Signaled Session Down—The remote end notifies the local end of BFD session down. · Administratively Down—The local system prevents a BFD session from being established. |
reset bfd session statistics
Use reset bfd session statistics to clear the BFD session statistics.
Syntax
reset bfd session statistics
Views
User view
Predefined user roles
network-admin
Examples
# Clear the BFD session statistics.
<Sysname> reset bfd session statistics
snmp-agent trap enable bfd
Use snmp-agent trap enable bfd to enable SNMP notifications for BFD.
Use undo snmp-agent trap enable bfd to disable SNMP notifications for BFD.
Syntax
snmp-agent trap enable bfd
undo snmp-agent trap enable bfd
Default
All SNMP notifications are enabled for BFD.
Views
System view
Predefined user roles
network-admin
Usage guidelines
To report critical BFD events to an NMS, enable SNMP notifications for BFD. For BFD event notifications to be sent correctly, you must also configure SNMP as described in the network management and monitoring configuration guide for the device.
Examples
# Disable SNMP notifications for BFD.
<Sysname> system-view
[Sysname] undo snmp-agent trap enable bfd
