sub vcl_hit {

if (obj.ttl < 1s) {
        return (pass);
}

if (req.http.Cache-Control ~ "no-cache") {
# Ignore requests via proxy caches,  IE users and badly behaved crawlers
# like msnbot that send no-cache with every request.
if (! (req.http.Via || req.http.User-Agent ~ "bot|MSIE|HostTracker")) {
        set obj.ttl = 0s;
        return (restart);
}
}

return (deliver);

}