Dell Force10 S25N-S50N FTOS Configuration Guide FTOS 8.4.2.7 E-Series TeraScal - Page 263

Change BGP timers Use either or both of the following commands in the CONFIGURATION ROUTER BGP mode to configure BGP timers. Command Syntax neighbors {ip-address | peer-group-name} timers keepalive holdtime timers bgp keepalive holdtime Command Mode CONFIG-ROUTERBGP CONFIG-ROUTERBGP Purpose Configure timer values for a BGP neighbor or peer group. • keepalive range: 1 to 65535. Time interval, in seconds, between keepalive messages sent to the neighbor routers. (Default: 60 seconds) • holdtime range: 3 to 65536. Time interval, in seconds, between the last keepalive message and declaring the router dead. (Default: 180 seconds) Configure timer values for all neighbors. • keepalive range: 1 to 65535. Time interval, in seconds, between keepalive messages sent to the neighbor routers. (Default: 60 seconds) • holdtime range: 3 to 65536. Time interval, in seconds, between the last keepalive message and declaring the router dead. (Default: 180 seconds) Use the show config command in CONFIGURATION ROUTER BGP mode or the show running-config bgp command in EXEC Privilege mode to view non-default values. Timer values configured with the neighbor timers command override the timer values configured with the timers bgp command. When two neighbors, configured with different keepalive and holdtime values, negotiate for new values, the resulting values will be as follows: • the lower of the holdtime values is the new holdtime value, and • whichever is the lower value; one-third of the new holdtime value, or the configured keepalive value is the new keepalive value. BGP neighbor soft-reconfiguration Changing routing policies typically requires a reset of BGP sessions (the TCP connection) for the policies to take effect. This type of reset causes undue interruption to traffic due to the hard reset of the BGP cache and the time it takes to re-establish the session. BGP soft reconfiguration allows you to re-apply policies to a session without resetting the BGP session. You can perform soft reconfiguration on a per-neighbor basis for either inbound or outbound policies. BGP soft reconfiguration clears and reapplies policies without resetting the TCP connection. Border Gateway Protocol IPv4 (BGPv4) | 263