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Misconfiguration of BGP update-source Behavior in PE-CE eBGP Peering ( %BGP-5-NBR_RESET )

714 views · Published 25 January 2015 · 11:29 · Indexed 21 September 2026

Channel: Travis Bonfigli · 2015 · Science & Technology

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This short video takes a look at the behavior between the PE-CE eBGP peering relationship when the update-source command specifies an interface not reachable between the eBGP peers.  Specifically, when the CE router is configured with the update-source address (in this case loopback 0) and that address isn't reachable from the PE router the peering relationship will fail to establish with the router logging the error: %BGP-5-NBR_RESET Keeping in mind that the update-source command in BGP, leveraging a loopback interface, is used when there are multiple paths to the other BGP peer.  In this case, there is only one link so the update-source isn't even needed, but if desired, should be set to the Ethernet0/0 interface.

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