Configure the UDP Port Forwarding List

Configure the UDP port forwarding list to assign protocols and servers to the port forward list.

About this task

You can perform this procedure in Global Configuration mode, VLAN Interface Configuration mode, or VRF Router Configuration mode.

Procedure

  1. Enter Global Configuration mode:

    enable

    configure terminal

  2. Configure the UDP port forwarding list:

    ip forward-protocol udp portfwdlist <1-1000>

    Important

    Important

    The following two steps are not available in the Global Configuration or VRF Router Configuration mode. The following two commands are available in VLAN Interface Configuration mode only.

  3. Enter VLAN Interface Configuration mode:

    interface vlan <1-4059>

  4. Configure the broadcast mask:

    ip forward-protocol udp broadcastmask {A.B.C.D}

  5. Configure the maximum time to live:

    ip forward-protocol udp maxttl <1-16>

  6. Confirm your configuration:

    show ip forward-protocol udp portfwdlist <1–1000> [vrf WORD<1-16>] [vrfids WORD<0-512>]

Example

Switch:1> enable
Switch:1# configure terminal

Configure the UDP port forwarding list:

Switch:1(config)# ip forward-protocol udp portfwdlist 1

Log on to the VLAN interface configuration mode:

Switch:1(config)# interface vlan 3

Configure the broadcast mask:

Switch:1(config-if)# ip forward-protocol udp broadcastmask 192.0.2.255

Configure the maximum time to live:

Switch:1(config-if)# ip forward-protocol udp maxttl 10

Confirm the configuration:

Switch:1(config-if)# show ip forward-protocol udp portfwdlist

Variable definitions

Use the data in the following table to use the ip forward-protocol udp portfwdlist command.

Variable

Value

<1-1000>

Creates a UDP port forwarding list in the range of 1–1000.

<1–65535> {A.B.C.D}

Adds a UDP protocol port to the specified port forwarding list.

1-65535 is a UDP protocol port in the range of 1–65535.

A.B.C.D is an IP address in a.b.c.d format.

Use the no operator to remove or delete a port forwarding list ID,

no ip forward-protocol udp portfwdlist <1-1000> <1-65535> <A.B.C.D>.

To configure this option to use the default value, use the default operator with this command.

name WORD<0–15>

Changes the name of the port forwarding list.

Use the data in the following table to use the ip forward-protocol udp command.

Variable

Value

broadcastmask {A.B.C.D}

Configures the interface broadcast mask (the interface broadcast mask can be different from the interface mask).

A.B.C.D is an IP address in a.b.c.d format.

Use the no operator to delete the broadcast mask:

no ip forward-protocol udp broadcastmask {A.B.C.D}

To configure this option to the default value, use the default operator with this command.

maxttl <1-16>

Configures the maximum time-to-live value (TTL) for the UDP broadcast forwarded by the interface. The range is 1–16.

portfwdlist <1–1000>

Assigns the list to the VLAN.

vlan <1-4059> [portfwdlist <1–1000>]

Specifies the VLAN ID in the range of 1 to 4059. By default, VLAN IDs 1 to 4059 are configurable and the system reserves VLAN IDs 4060 to 4094 for internal use. On switches that support the vrf-scaling and spbm-config-mode boot configuration flags, if you enable these flags, the system also reserves VLAN IDs 3500 to 3998. VLAN ID 1 is the default VLAN and you cannot create or delete VLAN ID 1.

If you use the portfwdlist variable with the VLAN variable, it assigns the list to the specified VLAN, regardless of which VLAN context you currently configure.