Did you ever add s second NIC in the server, I'm assuming it's a VM.
I had a session with TAC yesterday resolving an issue about no default GW. A second NIC was added temporarily and removed by the customer, the customer never had the courtesy to mention that.
So, anyway... TAC identified the second NIC config file, but there was no NIC installed, and the second NIC file configuration was taking precedence over the routing of traffic from the AMP server.
Seems to be specific to CentOS/Linux. Resolution involved, deleting the 2and NIC file and references to it, reconfigure the main NIC and reboot to test for config.
My customer's AMP is .11 version btw.