asymmetric routing issue cisco over the vpn tunnel

[Mujeeb]

Hi All , 

we have a situation where i found the asymmetric routing , we have two connectivity from the client network to the the data center , Primary connectivity is via the wan link and secondary  as vpn tunnel over the 4 G which terminate on watchGuard  . we are using ospf as a routing protocol .

Here is situation , when we are enabling the tunnel which is same Cisco box , some of the traffic goes the primary wan link and other from the tunnel . we wanted to setup a fail-over scenario where if the wan link goes down the tunnel take the lan traffic , In my case , sometimes the traffic is getting diverse and some time the return traffic is coming from the tunnel route . Please see the diagram as attached , need suggestion as the   asymmetric  routing impacting the lan traffic , At the moment i have disable the tunnel 

[chrihussey]

Hello,

In its simplest terms, if you are having asymmetric routing issues and are using OSPF, it is because it is seeing the WAN and VPN tunnel as equal cost or unfavorably seeing the VPN as a preferred path. This could easily be remedied by adjusting the interfaces' OSPF cost or bandwidths to prefer one over the other.

Your situation may be a little more complicated, but that is generally the quickest and easiest method.

Hope this helps.