Hello, My squid for reverse proxy has the config like: cache_peer 172.23.147.30 parent 80 0 no-query originserver name=RES acl service_res dstdomain res.mail.xx.com res_css.mail.xx.com res_js.mail.xx.com res_img.mail.xx.com res-css.mail.xx.com res-css.mai l.xx.com res-js.mail.xx.com res-img.mail.xx.com acl service_res dstdomain r7.mail.xx.com r7_css.mail.xx.com r7_js.mail.xx.com r7_img.mail.xx.com r7-css.mail.xx.com r7-js.mail.xx.co m r7-img.mail.xx.com cache_peer_access RES allow service_res When I stop and start Squid I get the warnings in screen: 2008/02/22 14:44:35| WARNING: 'res-css.mail.xx.com' is a subdomain of 'res-css.mail.xx.com' 2008/02/22 14:44:35| WARNING: because of this 'res-css.mail.xx.com' is ignored to keep splay tree searching predictable 2008/02/22 14:44:35| WARNING: You should probably remove 'res-css.mail.xx.com' from the ACL named 'service_res' My squid seems to work well though. But why this happened? thanks.