I am a programmer but have now a role looking after a linux based network so this question may be a little silly. All P.C.s go through squid as the proxy server, squid is not set to block the normal "trusted" ports e.g. 80 (http) and I have also changed it to allow higher ports e.g. 4040. but when I try to open a URL containing this port number squid blocks it, e.g.
any thoughts as to why it is doing this.
The clients are windows XP, squid is running on debian (afaik) on a VMware image.
Best Answer
Allowed ports are usually configured by the
Safe_ports
acl
. The configuration file should have an ACL configuring a ports list. This is used in anhttp_access
rule. My configuration has the rulehttp_access deny !Safe_ports
.The Debian system may be running an iptables firewall which prevents outgoing access to port 4040.
EDIT: It may be easier to read the configuration if you strip comments and blank lines from it. This should reduce the number lines you are looking at to under 50 or so. Commands to strip down the file and extract the acl data are:
Significant lines for your problem are:
Problem would most likely occur if unregistered ports are missing. Connection will likely fail if HTTPS is being used on the port.