← A multi-homed edge keeps choosing the wrong upstream

Lab

A live network, in your browser. Configure each device in the editor or its terminal, watch the topology converge, and run show, ping and traceroute, all computed from your config. Hit Check when it works.

Objectives

  • Met: Both eBGP sessions (to R2 and R3) are Established
  • Not met: R1's chosen route to 203.0.113.0/24 leaves through R2, even though both upstreams advertise it
  • Not met: Inbound traffic for 10.0.1.0/24 returns through R2 as well, because R3 sees R1's path as the less attractive one

1 of 3 objectives met.

10.0.12.0/3010.0.13.0/30r1r2r3
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R1>
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