asymmetric routing L3OUT and IPN/ISN

[Monfi190]

L3OUT and IPN/ISN connectivity termintaed on the same device. How do we prevent asymmetric routing for incoming traffic.

For example for traffic going to ACI site B, how do we make sure that retrun traffic use IPN/ISN link and not the L3OUT to reach ACI Site A?

OSPF is everywhere and no VRF.

Thanks,

HM

[Robert Burns · Accepted solution]

First, your ISN and L3out should be using different VRFs.  Second, whenver traffic needs to get from Site1 > Site2, it will ALWAYS prfer the ISN in the case where both sites have a local L3out.  There should be no way your L3out in Site1 should be able to connect to Site2 via the ISN.  

Robert