Please see attached picture. We are going to migrate interface e1/1 to e1/2 on R3(MX960) without downtime during the process. Now there is eBGP relation between R1 and R3. Here is the process: we need to copy all configurations of e1/1 to e1/2 on R3 and setup bgp between R2 and R3 and let e1/1 and e1/2 on R3 are up for a while during the cutover. My question is what bgp attribute we can use in R3 in order to switch traffi/routes from e1/1 to e1/2 on R3? Thank you
You could use higher local-preference to prefer received routes [outbound traffic] and different AS-PATH pre-pend or MED [assuming peering with same ASN] for advertised routes.
However by copying config from e1/1 to e1/2, will you not be duplicating the ip address on the interface?
Yes, I agree. Thank you