Configure multiple sites with Varnish

Question

We have a server which needs to serve multiple domains though varnish e.g. example1.com, example2.com and example3.com

Our current .vcl file looks like this:

Answer 1

I'm using setup similar to Cristian's, but in if clauses I match req.http.host against regular expression:

#for www.example.com or example.com
if (req.http.host ~ "^(www\.)?example\.com$") {
        set req.backend = example_com;
        return (lookup);
}

#with any subdomain support
if (req.http.host ~ "^(.*\.)?example2\.com$") {
        set req.backend = example2_com;
        return (lookup);
}

Don't forget to set backends appropriately!