Cisco Cisco IOS Software Release 12.2(27)SBC

This section contains the following procedures:

 (required)

 (optional)

Perform this task to enable a PE router to maintain BGP state with CE routers and ensure continuous 
packet forwarding during a RP switchover or during a planned ISSU. BGP NSR with SSO enables 
service providers to provide the benefits NSF with the additional benefits of NSR without requiring CE 
routers to be upgraded to support BGP graceful restart. 

BGP NSR with SSO is supported in BGP peer, BGP peer group, and BGP session template 
configurations. Perform one of the following tasks in this section on a PE router, depending on whether 
you want to configure support for BGP NSR with SSO in a peer, a peer group, or a session template 
configuration:

These tasks assume that you are familiar with BGP peer, BGP peer group, and BGP session template 
concepts. For more information, see the “

” chapter in the 

Cisco IOS IP Routing Configuration Guide, Release 12.4.

The active and standby RP must be in SSO mode. For information about configuring SSO mode, see 
the “Configuring SSO” task in the

 document.

Graceful restart should be enabled on the PE router. For more information about configuring 
graceful restart, see the “

” document.

We recommend that you enable graceful restart on all BGP peers in the provider core that 
participate in BGP NSF. 

CE routers must support the route refresh capability. For more information, refer to the “

” part 

of the Cisco IOS IP Configuration Guide, Release 12.4.

This feature is supported only on Cisco 10000 Series PRE2s and Cisco 10000 Series PRE3s.