There are a couple of things in your environment that are not clear to me. I gather that the devices in the drawing on the left and on the right are routers of some kind. Is the 5500 in the center functioning just as a layer 2 switch or is it also doing layer 3?
You comment that all routes in the routing table are connected. Do I understand that the router on the left has only a single route in its table 10.10.160.0/26? And do I understand that the router on the right has only two routes in its table (10.10.160.0/26 and 10.10.160.64/26? And do I assume correctly that there is no dynamic routing protocol configured?
If my understanding is correct then there are at least two solutions that you can consider. You could configure a static route on the left router that would look something like this:
ip route 10.10.160.64 255.255.255.192 10.10.160.59
Or you could configure some dynamic routing protocol on both routers, including both subnets of the right router in the routing protocol.
Either of these solutions would allow the 10.10.160.2 machine to ping the 10.10.160.66 machine. Having the default gateway set to 10.10.160.58 is appropriate and is not itself a problem. The problem in your current environment is that the router on the left has no knowledge of the 10.10.160.64 subnet or how to get there. This is the problem that you must resolve.
HTH
Rick
HTH
Rick
