12-1. synchronization

Syntax Description:

This command has no arguments.

Purpose: IBGP learned routes are not installed in the IP routing table if the route has not been learned by an IGP or if the advertised next hop is inaccessible. This is called synchronization.

IOS Release: 10.0

Configuration Example: BGP Synchronization

In Figure 12-1, BGP synchronization is enabled by default. Router A is advertising network 199.172.1.0/24 to Router B via EBGP, and Router B is advertising 199.172.1.0/24 to Router C via IBGP.

Figure 12-1. Synchronization Applies to IBGP Routes

Router A
interface Loopback0
 ip address 199.172.1.1 255.255.255.0
!
router bgp ...

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