Modifying the BGP router ID

Changing the router ID number in the BGP context causes the new value to overwrite the router ID configured on the router level, system interface level, or the value inherited from the MAC address. Changing the router ID on a router could cause configuration inconsistencies if associated values are not also modified.

When configuring a new router ID, protocols are not automatically restarted with the new router ID. The next time BGP is (re) initialized the new router ID is used. To force the new router ID, issue the shutdown and no shutdown commands for BGP or restart the entire router.

Example: Command usage to configure a new router iD

config>router>bgp# router-id 10.0.0.104
     config>router>bgp# shutdown
     config>router>bgp# router-id 10.0.0.123
     config>router>bgp# no shutdown

Example: BGP configuration output

The following is a sample BGP configuration output with the BGP router ID specified.

ALA-B>config>router>bgp# info detail
----------------------------------------------
no shutdown
no description
no always-compare-med
ibgp-multipath load-balance
. . . 
router-id 10.0.0.123
----------------------------------------------
ALA-B>config>router>bgp#