Hi Rene
I have a routing issue in production so I have setup a GNS lab similar to the production and GNS has the same issue. I will explain the problem in word first in case you have easy solution if not, then I am happy to send you GNS topology.
We have three services provider. ISP A , ISP B & ISP C
ISP A running RIP v2
ISP B running Layer 2 connection so we don’t have to worry about their protocol, both sites has point to point connectivity. (Currently active but we are going to decommissioned)
ISP C running BGP (not Active yet as we have a routing issue but this is the one we are forcing to use in near future)
Our network is divided into two sites, Site 1 & Site 2, both site is reasonably big, running EIGRP.
Both sites have approx… 50 to 60 subnets.
Our 2 ASR from each site connected to ISP A running EIGRP & RIP, we have mutual redistribution at both site such as RIP to EIGRP vice versa. Majority of traffic going thru our WAN link with ISP B as both site have EIGRP AD 90, and if ISP B fail then traffic failover to ISP A with AD 170. All working nicely at the moment.
Now we are going to decommission WAN link of ISP B and commission WAN link with ISP C.
I have setup the GNS lab which is mirror the production.
My configuration detail as follows:
I am redistributing RIP route from ISP A to EIGRP vice versa on both site 1 & 2.
Also I am redistributing BGP route from ISP C to EIGRP vice versa on both site 1 & 2.
Both sites have route to each other with AD 170 & if any of WAN link fail, the traffic failover to another link.
Now the problem I am facing as follows:
I want to force traffic via WAN link of ISP C (which is running BGP) as this is 1GIG link and ISP A has 100MB link.
Because of redistribution from both ISP, our sites have EIGRP route with AD 170.
I have use route-map to lower the metric so route from ISP C has better metric and I have test it by turning off link one by one that Site 1 has better metric from ISP C to reach site 2 vice versa.
Routing work nicely such as if any link fail then it’s failing over to another link.
Now the real problem is if I turn off WAN link of ISP C then it’s failover to ISP A but when I turn back on ISP C then traffic not failing over to ISP C 1 GIG link. Sometime one site redirect the traffic to ISP C but other site keep using slow link at ISP A. Having asymmetric issue.
I want both sites to use ISP C when ISP A WAN is open.
Let me know if you need config file or GNS topology.
Thank you.
Vinod