I have a remote site that is connected using a LAN-to-LAN tunnel. They have a 2610XM and are connected back to our core through a 3030 concentrator. The connection is working fine, however, every now and then, the tunnel will drop and reestablish itself. It always comes back up just fine and no one loses anything. However, every now and then, the ethernet segment will stop communicating through the tunnel. In other words, I can't ping the ethernet interface. I can ping the loopback interface, though. Since our monitoring software monitors via the loopback interface, it assumes the router is up (which technically it is). The solution that I have discovered is to dial into the router with a modem and reapply the access list that defines tunnel traffic. This works every time. Has anyone seen anything like this?
