Configuring a BGP ConnectRetry Timer

You can control the speed at which BGP peer relationships are established by changing the BGP ConnectRetry timer value.

Context

After BGP initiates a TCP connection, the ConnectRetry timer will be stopped if the TCP connection is established successfully. If the first attempt to establish a TCP connection fails, BGP re-establishes the TCP connection after the ConnectRetry timer expires.

Setting a short ConnectRetry interval reduces the period BGP waits between attempts to establish a TCP connection, which speeds up the establishment of the TCP connection.
Setting a long connectRetry interval suppresses routing flapping caused by peer relationship flapping.

A ConnectRetry timer can be configured either for all peers or peer groups, or for a specific peer or peer group. A ConnectRetry timer configured for a specific peer takes precedence over that configured for the peer group of this peer. In addition, a ConnectRetry timer configured for a specific peer or peer group takes precedence over that configured for all peers or peer groups.

Procedure

Configure a BGP ConnectRetry timer for all peers or peer groups.
Perform the following steps on a BGP router:
1. Run system-view
  The system view is displayed.
2. Run bgp as-number
  The BGP view is displayed.
3. Run timer connect-retry connect-retry-time
  A BGP ConnectRetry timer is configured for all peers or peer groups.
4. Run commit
  The configuration is committed.
Configure a BGP ConnectRetry timer for a peer or peer group.
Perform the following steps on a BGP router:
1. Run system-view
  The system view is displayed.
2. Run bgp as-number
  The BGP view is displayed.
3. Run peer { group-name | ipv4-address } timer connect-retry connect-retry-time
  A BGP ConnectRetry timer is configured for a peer or peer group.
4. Run commit
  The configuration is committed.