varnish 负载首页到CMS系统

if ( req.http.host ~ "(?i)xxxx.com" && 

req.request == "GET" &&

( req.url ~ "^/(|\?[^/]*)$" 

|| req.url ~ "^/index.html" )){

set req.url = "/index.html";

set req.backend = cms_httpd_director;

}else{

            set req.backend = ihs_director;

}