Varnish serving content from wrong backend

[Michael Alger]

On Tue, Oct 11, 2011 at 10:28:43AM -0300, Paulo Paracatu wrote:
> It seems there is something broken in my Varnish configuration
> files.  I have two Varnish servers running and 14 backend servers.
> The first backend loaded in the VCLs is the 's105', which host
> several adult (including hentai) sites, and after it it loads the
> other 13 backends, hosting several wordpress blogs and invision
> board forums.

The first backend Varnish loads will be the default backend, i.e.
where requests are sent if you don't explicitly set req.backend in
vcl_recv. It sounds like you might not be correctly setting your
backend when processing requests.

Can you provide your VCL, or at least a representative sample of how
you're mapping your sites to backends?

If you're relying on host headers, are you properly handling all
possibilities? e.g. some browsers might send the port number so you'll
get something like "Host: www.some.site:80" which maybe you're not
handling (expecting only "www.some.site") and therefore it's going
through to the default backend.