Varnish setup

Varnish setup

This is a quick guide to cache tiles using varnish.

Newest update to the vcl scripts can be found here https://github.com/klausdk/varnish/tree/master/openstreetmap

DNS setup

You will need a ip dedicated to varnish to run on port 80

Create 3 dns entries :

a.tile.host.tld -> Your ip / host
b.tile.host.tld -> Your ip / host
c.tile.host.tld -> Your ip / host

Install varnish

Assuming redhat/centos :

rpm --nosignature -i http://repo.varnish-cache.org/redhat/varnish-3.0/el5/noarch/varnish-release-3.0-1.noarch.rpm
yum install varnish  

Checkout https://www.varnish-cache.org/releases for other ways to install

vcl script for varnish 3.0 (file.vcl)

This script is designed only to cache tiles for openstreetmap.

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


backend a_tile {
  .host = "a.tile.openstreetmap.org";
  .port = "80";
}

backend b_tile {
  .host = "b.tile.openstreetmap.org";
  .port = "80";
}

backend c_tile {
  .host = "c.tile.openstreetmap.org";
  .port = "80";
}

sub vcl_recv {

  if (req.http.host ~ "^a.tile") {
    set req.backend = a_tile;
  } else if (req.http.host ~ "^b.tile") {
    set req.backend = b_tile;
  } else if (req.http.host ~ "^c.tile") {
    set req.backend = c_tile;
  }

  remove req.http.cookie;

  // Cache everything
  if (req.request == "GET") {
    return (lookup);
  }


}

sub vcl_fetch {

  // Cache tiles for 3 weeks
  set beresp.ttl = 3w;

  // Remove all cookies
  remove beresp.http.set-cookie;
  remove beresp.http.cookie;

}

sub vcl_deliver {

        
  if (obj.hits > 0) {
    set resp.http.X-Cache_v = "HIT";
  } else {
    set resp.http.X-Cache_v = "MISS";
  }
}

sub vcl_hash {

  // Cache using only url as a hash.  
  // This means if a.tile/1/1/1/tile.png is accessed, b.tile/1/1/1/tile.png will also be fetch from cache
  hash_data(req.url);
  return (hash);
}

vcl script for varnish 4.0 (file.vcl)

vcl 4.0;

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


backend a_tile {
  .host = "a.tile.openstreetmap.org";
  .port = "80";
}

backend b_tile {
  .host = "b.tile.openstreetmap.org";
  .port = "80";
}

backend c_tile {
  .host = "c.tile.openstreetmap.org";
  .port = "80";
}

sub vcl_recv {

  if (req.http.host ~ "^a.tile") {
    set req.backend_hint = a_tile;
  } else if (req.http.host ~ "^b.tile") {
    set req.backend_hint = b_tile;
  } else if (req.http.host ~ "^c.tile") {
    set req.backend_hint = c_tile;
  } else if (req.http.host ~ "^a.map") {
    set req.backend_hint = a_tile;
  } else if (req.http.host ~ "^b.map") {
    set req.backend_hint = b_tile;
  } else if (req.http.host ~ "^c.map") {
    set req.backend_hint = c_tile;
  }

  unset req.http.cookie;

  // Cache everything
  if (req.method == "GET") {
    return (hash);
  }


}

sub vcl_backend_response {

  // Cache tiles for 3 weeks
  set beresp.ttl = 3w;

  // Remove all cookies
  unset beresp.http.set-cookie;
  unset beresp.http.cookie;

}

sub vcl_deliver {

        
  if (obj.hits > 0) {
    set resp.http.X-Cache_v = "HIT";
  } else {
    set resp.http.X-Cache_v = "MISS";
  }
}

sub vcl_hash {

  // Cache using only url as a hash.  
  // This means if a.tile/1/1/1/tile.png is accessed, b.tile/1/1/1/tile.png will also be fetch from cache
  hash_data(req.url);
  return (lookup);
}

Start up

varnishd -a yourip:80 -f /etc/varnish/file.vcl