# Configuring ANCP

ANCP uses several global-level configuration commands to enable ANCP to function on the router.

## Creating a Listening TCP Socket for ANCP

Use the l2c ip listen command to create a listening TCP socket for ANCP. ANCP monitors port 6068 for ANCP TCP connection requests.

l2c ip listen

- Use to create a listening TCP socket in the current virtual router context.
- Example
  host1(config)#l2c ip listen
- Use the no version to remove the listening TCP socket and stop any new sessions from being established. The no version does not terminate any existing GSMP sessions.
- See l2c ip listen.

## Accessing L2C Configuration Mode for ANCP

Use the l2c command to launch the L2C Configuration (config-l2c) mode for ANCP. In this mode, you can define session timeout values and access the L2C Neighbor Configuration mode to configure an ANCP neighbor.

l2c

- Use to launch the L2C Configuration (config-l2c) mode for ANCP.
- Example
  host1(config)#l2c host1(config-l2c)#
- Use the no version to remove all ANCP configurations.
- See l2c.

## Defining the ANCP Session Timeout

In L2C Configuration (config-l2c) mode, you can use the session-timeout command to specify the ANCP session timeout value. The timer range is 1–25 seconds with a default value of 25 seconds.

session-timeout

- Use to define the ANCP session timeout value (in seconds).
- Example
  host1(config-l2c)#session-timeout 10
- Use the no version to revert the session timeout to its default setting, 25 seconds.
- See session-timeout.

## Learning the Access Node Partition ID

In L2C Configuration (config-l2c) mode, you can use the wait-for-gsmp-syn command to enable the learning option. This learning option in the virtual router enables network access server to learn the partition ID from all the access nodes.

wait-for-gsmp-syn

- Use to enable the learning option in ANCP.
- Example
  (config-l2c)# wait-for-gsmp-syn
- Use the no version to disable the learning option in ANCP.

If the access node does not send the GSMP_SYN message after initiating the TCP session, the connection is lost because the session timer expires. To avoid this, you can use the gsmp-syn-timeout command to specify the timeout value in L2C Configuration (config-l2c) mode. The timer value cannot be more than the ANCP session timeout value with a default value of 60 seconds.

gsmp-syn-timeout

- Use to define the TCP session timeout value (in seconds).
- Example
  (config-l2c)# gsmp-syn-timeout 10
- Use the no version to revert the session timeout to its default setting, 60 seconds.