I have been looking for information relating to the configuration of WCCP in relation to standard client side NAT of private addresses. NAT order of operations gives some indication of how it works but I am wondering if there is any recommended guidelines to insure NAT and WCCP function correctly with the desired outcome being both non NAT and NATed traffic is accelerated.
I have attached a diagram for reference.
In Scenerio 1.
Redirection is WCCP GRE/IP Forwarding,
The WAE is on its own subnet.
A redirection list only redirects traffic between the DC and the BO public range (including NAT global) on the WAN interface (in and out).
Internal Public non-Nat'ed traffic shows up in the connection statistics optimized but the NAT global addresses show up on the DC WAE as "PT no Peer"
In Scenerio 2.
Redirection out of the WAN interface is moved to (in) the LAN interface of the router and the redirect ACL is expanded to include ANY-DC, DC-ANY ( including the private 172.x.x.x/xx range)
This breaks NAT. I assume because wccp occurs before NAT (inside-outside).
From the information I have found I guess
1. Redirection should be oubound in one direction (WAN interface) if IP CEF is enabled ?
2. the WAE interface should be in NAT inside and the redirect ACL include the private inside range ?
Thanks for any advice.