On 23/10/2015 10:43 a.m., Job wrote: > Hello, > > sometimes, for about half an hour, tour Squid becomes unstable and, by typing "top -s", Squid is taking the 100% of the CPU. > > In Squid's access.log, i see lots of entry like this: > > "Thu";"Oct";"22";"11:45:17";"2015";"21328";"192.168.1.250";"TCP_MISS/000";"0";"GET";"http://192.168.1.254:8080/cgi-bin/a2/out.cgi";"-";"DIRECT/192.168.1.254";"-" > "Thu";"Oct";"22";"11:45:18";"2015";"19153";"192.168.1.250";"TCP_MISS/000";"0";"GET";"http://192.168.1.254:8080/cgi-bin/a2/out.cgi";"-";"DIRECT/192.168.1.254";"-" > "Thu";"Oct";"22";"11:45:18";"2015";"20346";"192.168.1.250";"TCP_MISS/000";"0";"GET";"http://192.168.1.254:8080/cgi-bin/a2/out.cgi";"-";"DIRECT/192.168.1.254";"-" > "Thu";"Oct";"22";"11:45:21";"2015";"20391";"192.168.1.250";"TCP_MISS/000";"0";"GET";"http://192.168.1.254:8080/cgi-bin/a2/out.cgi";"-";"DIRECT/192.168.1.254";"-" > "Thu";"Oct";"22";"11:45:21";"2015";"19142";"192.168.1.250";"TCP_MISS/000";"0";"GET";"http://192.168.1.254:8080/cgi-bin/a2/out.cgi";"-";"DIRECT/192.168.1.254";"-" > "Thu";"Oct";"22";"11:45:22";"2015";"19075";"192.168.1.250";"TCP_MISS/000";"0";"GET";"http://192.168.1.254:8080/cgi-bin/a2/out.cgi";"-";"DIRECT/192.168.1.254";"-" > > There seem be a possible attack/exploit from an internal machine? It is the 192.168.1.250 in the example. > > Is there a patch or something to not spread up Squid to the 100% cpu limit for these "Attacks"? > That looks like the side effects of a forwarding loop DoS. Look for the following line in your squid.conf and remove it: via off That should return to Squid its ability to actually detect and abort looping behaviour quickly and let you find the real problem. I suspect it is a bad NAT configuration. Amos _______________________________________________ squid-users mailing list squid-users@xxxxxxxxxxxxxxxxxxxxx http://lists.squid-cache.org/listinfo/squid-users