Unable to Connect (Inbound and Outbound) across CBAC
If you are unable to connect to the Internet or from the Internet to the internal network across a CBAC router, you need to first find out if there is any session created (upon seeing the first request packet the inspection engine creates a session). If the session is created, check the state of the session by executing show ip inspect session on the router. If there is no session, the packet is not even reaching the inspection engine. Among many, the following are some of the common causes of this problem: