As far as I know the advanced IP services image c2600-advipservicesk9-mz.123-6e should support VPN just fine.
Just to clarify one aspect, your message talks about VPN between two concentrators and talks about 837 and 2651. Am I correct that the 837 and the 2651 are the concentrators doing the VPN?
Your message says the VPN is established so I assume that it is not an issue with configuration of the VPN. If the 837 is sending but the 2651 is not responding I can think of a few things that might cause this:
- are the packets perhaps leaving the 837 but not getting to the 2651? (one way to check this would be to turn on debug icmp on the 2651 and then ping the 2651 from the 837.)
- if the packets do get to the 2651 it might be possible that it does not have a correct route back to the 837. (the output of show ip route should clarify that.)
- if you are doing NAT there might be something in the NAT configuration that is getting in the way of successful communication.
If you could provide a little information about the topology of the network (what addresses are where and how are things connected) and post the configs we might be able to help you find the issue.
HTH
Rick
HTH
Rick
