RE: [squid-users] Going into hit-only-mode for 5 minutes... and wrong urls

>
> On 1/08/2012 6:01 p.m., Dmitry Melekhov wrote:
> > Hello!
> >
> > I switched to 3.HEAD-20120627-r12185 from 2.6 two days ago and now I
> > see in log something like:
> >
> >
> > 2012/08/01 08:25:48 kid1| Failed to select source for
> > 'http://izavia.su/favicon.ico'
> > 2012/08/01 08:25:48 kid1| always_direct = DENIED
> > 2012/08/01 08:25:48 kid1| never_direct = DENIED
> > 2012/08/01 08:25:48 kid1| timedout = 0
> > 2012/08/01 08:28:47 kid1| Failure Ratio at 1.017
> > 2012/08/01 08:28:47 kid1| Going into hit-only-mode for 5 minutes...
> >
> >
> > Yes, this is situation described in FAQ, but this is just wrong url-
> > user mistake, not DNS or connectivity problem.
> > Is there any way to avoid this?
>
> It *is* a DNS problem. Out of *all* recent requests 101 out of the last
> 102 requests failed to resolve or did resolve and TCP conection to them
> failed. Regardless of the reason being users pounding your Squid at high
> speed with non-existent URLs or connectivity being down - you have a
> problem outside of Squid to fix.
>

So just to get this straight... my users could DoS my squid by sending lots of requests for invalid dns entries? In what versions does this exploit exist?

James

Received on Wed Aug 01 2012 - 07:16:52 MDT