Squid can both be used a proxy and as a cache (reverse proxy) server. In my job, it's always as the latter I meet this server.
All requests are returned with invalid HTTP header etc
The access log file looks like this:
TCP_DENIED/400 1414 GET error:invalid-requestTCP_DENIED/400 1414
GET error:invalid-request
Solution: the acl list configuration in
squid.conf
listed a wrong IP address.