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BGP Multihop

  • eBGP defaults to a TTL of 1

Useful to peer eBGP neighbors to loopbacks instead of Link IPs.

Topology

     ┌─────────── eBGP ────────────┐      
     ▼                             ▼      
    Lo0                           Lo0     
10.0.0.96/32                  10.0.0.11/32
 ┌────────┐                    ┌────────┐ 
 │   R1   ├────────────────────┤  ISP   │ 
 │AS 64496│.0                .1│AS 64511│ 
 └────────┘   192.168.0.0/31   └────────┘ 

Config

!
! R1 needs some kind of route to know how to reach the loopback.
!
ip route 10.0.0.11 255.255.255.255 192.168.0.1
!
router bgp 64496
  neighbor 10.0.0.11 remote-as 64511
  neighbor 10.0.0.11 ebgp-multihop 2

References

Cisco - Connecting to a Service Provider Using External BGP - IP Routing Configuration Guide, Cisco IOS XE 17.x

Last Modified • Saturday, June 27, 2026. 11:45 pm UTC+00:00 • Commit: 4314778