Jauder Ho - links and things

Decided to try varnish, the relatively new squid alternative out. Here’s what I have so far. I’m getting about 66% (very limited testing, YMMV) cache hits with this setup but am missing some things for caching Rails sessions and content. With appropriate tuning/configuration, I am sure the hit rate could be much higher. If you have any suggestions, let me know and I will update this.

# Varnish Config

# default backend config
backend default {
	set backend.host = "127.0.0.1";
	set backend.port = "80";
}

# only allow purging of cache from localhost
acl purge {
  "localhost";
}

# this is the main config
sub vcl_recv {

  # Host header check.
  # * Check if we recognize the domain used
  # * Normalize host headers to limit cache usage
  # * Rewrite URL for the virtual host monster
  # Return an error for other requests.


  # cache multimedia
  if (req.request == "GET" && req.url ~ "\.(jpg|jpeg|gif|ico)$") {
    lookup;
  }	

  # cache CSS and JS files
  if (req.request == "GET" && req.url ~ "\.(css|js)$") {
    lookup;
  }	

  # cache static files
  if (req.request == "GET" && req.url ~ "\.(pdf|xls|vsd|doc|ppt|iso)$") {
    lookup;
  }	

  # do not cache POST requests
  if (req.request == "POST") {
    pipe;
  }

  if (req.request != "GET" && req.request != "HEAD") {

    # figure out if you are allowed to purge stuff from cache
    if (req.request == "PURGE") {
      if (!client.ip ~ purge) {
        error 405 "Not allowed.";
      }
      lookup;
    }

    # else just pass it along
    pipe;
  }

  if (req.http.Expect) {
    pipe;
  }

  if (req.http.If-None-Match) {
    pass;
  } 

  # pass to backend if we have HTTP authentication
  if (req.http.Authenticate || req.http.Authorization) {
    pass;
  }

  # We only care about the "__vu_*" cookies, used for authentication
#  if (req.http.Cookie && req.http.Cookie ~ "__vu_session=") {
#    pass;
#  }  

  # Remove the "Cookie:" header from the request.
#  remove req.http.cookie;

  # Do a "lookup" in the cache.  This goes to "vcl_hit", or to
  # "vcl_miss" and then "vcl_fetch"
  lookup;

}

sub vcl_hit {
  if (req.request == "PURGE") {
    set obj.ttl = 0s;
    error 200 "Purged.";
  }
}

sub vcl_miss {
  if (req.http.If-Modified-Since) {
    pass;
  }

  if (req.request == "PURGE") {
    error 404 "Not in cache.";
  }
}

sub vcl_fetch {
  # Handle X-Accel-Redirect
  if ( obj.http.x-accel-redirect ~ ".*" ) {
     set req.url = obj.http.x-accel-redirect;
     restart;
  }
}