We have implemented WCCP between Cisco router and Bluecoat cache engine, there's a ASA placed in between so we have configured the firewall to allow ports (UDP 2048, & GRE) in order for the WCCP sessions to be established.
The WCCP sessions is being established but transparent proxy is not working, it seems that the firewall is blocking the users traffic since the router is redirecting, putting in mind that everything was working fine before we put the firewall in place, below the ACL configured on the ASA:
access-list 100 line 24 extended permit gre <Router IP> <Cache Engine IP>
access-list 100 line 25 extended permit udp <Router IP> <Cache Engine IP> eq 2048
WCCP Information on the Router:
Service Identifier: 20
Number of Cache Engines: 1
Number of routers: 1
Total Packets Redirected: 378
Redirect access-list: 190
Total Packets Denied Redirect: 1317809
Total Packets Unassigned: 1832
Please advice what could be the cause of that and if is there any additional configuration needs to be done on the firewall?