We had a VPN tunnel from our Cisco firewall going to the firewall of another party, and it's been working fine for quite some time. However, the other party recently requested that we change the peer address, due to them making some changes with their internet provider.
We changed the address in the config, in all places that the old address existed. We also adjusted the access lists and any other areas where you'd find the old address.
Now, we are unable to initiate VPN traffic from our side. The other side can bring the tunnel up, and it stays up for the length of it's keepalive, but then it times out, and we're dead again.
Since the tunnel can be brought up from the other side, it stands to reason that the security is still correct, the peer IP address is good, etc. The other side claims to be configured for bi-directional setup.
Any thoughts as to why we can't bring up the tunnel from our side now, when all that's changed is the peer?