When cleaning the cache on varnish 3.0 there is a way to only ban the specific host.
The command is:
varnishadm -T localhost:1234 ban req.http.host ~ “site.com” && req.url ~ …
How to install varnish
How to install varnish
This is a step-by-step on howto setup and run varnish web cache.
This was done for Linux RedHat 6 64bits, same works for CentOS 5.5 64bits …