hello zoolabus,
Have you enable transparent redirection on the WSA ? Please check Network ->transparent redirection.
The WSA has to listen on the ports for it to act on this traffic.
You can find wccp config for routers, switches,ASA etc . Please check if this config is correct. make sure you are redirecting to the P1 interface. If its an ASA or FTD, WSA and the Clients should be behind the same interface of the device.
if all the above is correct and it still not working, check for access logs. check if the WSA is receiving this traffic or not.
Regards
Shikha Grover
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