I have been talking with developers on the squid-dev list about issues with havign both tproxy and interception enbaled on the same listen port when using WCCP, Squid 3.1 (squid 3 HEAD), and TProxy 4.1.0. The discussion revolves around the following errors in cache.log:
 
2008/07/25 12:38:57| IPInterception.cc(171) NetfilterTransparent:  NF getsockopt(IP_TRANSPARENT) failed: (92) Protocol not available
2008/07/25 12:47:12| IPInterception.cc(137) NetfilterInterception:  NF getsockopt(SO_ORIGINAL_DST) failed: (11) Resource temporarily unavailable
 
And occasional (99) errors seen by the client. It had been mentioned that interception and tproxy options should not be used together in a WCCP setup, but there is confusion as to how to seperate them, mush less if it is really required.
 
Anyone have comments on this?
 
Nick