UDP Helper configuration commands 1

display udp-helper server 1

reset udp-helper packet 1

udp-helper enable· 2

udp-helper port 2

udp-helper server 3

 

display udp-helper server

Syntax

display udp-helper server [ interface interface-type interface-number ] [ | { begin | exclude | include } regular-expression ]

View

Any view

Default level

2: System level

Parameters

interface interface-type interface-number: Displays information of forwarded UDP packets on the specified interface.

|: Filters command output by specifying a regular expression. For more information about regular expressions, see Fundamentals Configuration Guide.

begin: Displays the first line that matches the specified regular expression and all lines that follow.

exclude: Displays all lines that do not match the specified regular expression.

include: Displays all lines that match the specified regular expression.

regular-expression: Specifies a regular expression, a case-sensitive string of 1 to 256 characters.

Description

Use the display udp-helper server command to display the information of forwarded UDP packets on the specified interface or all interfaces.

If interface-type interface-number is not specified, this command displays the information of forwarded UDP packets on all interfaces.

Examples

# Display the information of forwarded UDP packets on the interface GigabitEthernet 3/1/1.

<Sysname> display udp-helper server interface GigabitEthernet 3/1/1

 Interface name         Server address      Packets sent

 GigabitEthernet3/1/1           192.1.1.2           0

The information above shows that the IP address of the destination server corresponding to the interface GigabitEthernet 3/1/1 is 192.1.1.2 and that no packets are forwarded to the destination server.

reset udp-helper packet

Syntax

reset udp-helper packet

View

User view

Default level

2: System level

Parameters

None

Description

Use the reset udp-helper packet command to clear the statistics of UDP packets forwarded.

Related commands: display udp-helper server.

Examples

# Clear the statistics of the forwarded UDP packets.

<Sysname> reset udp-helper packet

udp-helper enable

Syntax

udp-helper enable

undo udp-helper enable

View

System view

Default level

2: System level

Parameters

None

Description

Use the udp-helper enable command to enable UDP Helper. The router enabled with UDP Helper serves as a relay agent that converts UDP broadcast packets into unicast packets and forwards them to a specified destination server.

Use the undo udp-helper enable command to disable UDP Helper.

By default, UDP Helper is disabled.

Examples

# Enable UDP Helper

<Sysname> system-view

[Sysname] udp-helper enable

udp-helper port

Syntax

udp-helper port { port-number | dns | netbios-ds | netbios-ns | tacacs | tftp | time }

undo udp-helper port { port-number | dns | netbios-ds | netbios-ns | tacacs | tftp | time }

View

System view

Default level

2: System level

Parameters

port-number: UDP port number with which packets need to be forwarded, in the range of 1 to 65535 (except 67 and 68).

dns: Forwards DNS data packets. The corresponding UDP port number is 53.

netbios-ds: Forwards NetBIOS data packets. The corresponding UDP port number is 138.

netbios-ns: Forwards NetBIOS name service data packets. The corresponding UDP port number is 137.

tacacs: Forwards terminal access controller access control system (TACACS) data packet. The corresponding UDP port number is 49.

tftp: Forwards TFTP data packets. The corresponding UDP port number is 69.

time: Forwards time service data packets. The corresponding UDP port number is 37.

Description

Use the udp-helper port command to enable the forwarding of packets with the specified UDP port number.

Use the undo udp-helper port command to remove the configured UDP port numbers.

By default, no UDP port number is specified.

Note that:

·           You can configure up to 256 UDP ports on a router.

·           The specified UDP port numbers will all be removed if UDP Helper is disabled.

Examples

# Forward broadcast packets with the UDP destination port number 100.

<Sysname> system-view

[Sysname] udp-helper port 100

udp-helper server

Syntax

udp-helper server ip-address

undo udp-helper server [ ip-address ]

View

Interface view

Default level

2: System level

Parameters

ip-address: IP address of the destination server, in dotted decimal notation.

Description

Use the udp-helper server command to specify the destination server which UDP packets need to be forwarded to.

Use the undo udp-helper server command to remove the destination server.

No destination server is configured by default.

Note that:

·           You can configure up to 20 destination servers on an interface.

·           You will remove all the destination servers on an interface if you carry out the undo udp-helper server command without the ip-address argument.

Related commands: display udp-helper server.

Examples

# Specify the IP address of the destination server as 192.1.1.2 on the interface GigabitEthernet 3/1/1.

<Sysname> system-view

[Sysname] interface GigabitEthernet 3/1/1

[Sysname-GigabitEthernet3/1/1] udp-helper server 192.1.1.2