[squid-users] TCP_MISS/502

[Amos Jeffries]

On 18/11/2015 3:07 a.m., Ачилов Рашид Нурмухамедович wrote:
> How do you do.
> 
> When accessing to site http://www.ycmcnc.com through Squid 3.5.x (tried
> 3.5.2 and 3.5.11) immediately at first try occured TCP_MISS/502:
> 
> 1447767437.903    585 10.87.1.133 TCP_MISS/502 4267 GET
> http://www.ycmcnc.com/ - HIER_DIRECT/59.125.8.218 text/html
> 
> When tried access without proxy all OK. When tried access with old Squid
> 2.7-STABLE9 all OK. Troubles occured when tried through Squid 3.5.x.
> 

The server PHP scripts are apparently crashing whenever it receives the
*valid* X-Forwarded-For header of the type which gets emitted when you
configure:

> forwarded_for off


I can also reproduce the same crash/terminate behaviour when most other
perfectly valid XFF header are sent. The web developer who authored that
site is very ignorant of how X-Forwarded-For is used.


To work around this either remove the forwarded_for directive
completely. Or set it to another value than "off".
see <http://www.squid-cache.org/Doc/config/forwarded_for/>

Given the set of things that cause the server to die. You are probably
best going with truncate or delete.

Amos