4. Varnish: What
Reverse proxy
1. request 2. MISS
Visitor #1 Varnish Web app
4. response 3. response
Web app
1. request
Visitor #2 Varnish
zzzzzz
zzzzzzz
2. HIT zzzzz
http://www.mugo.ca
5. Varnish: What
https://www.varnish-cache.org/
Example: Varnish on port 80; Apache on port
88
Serve HTTP GET requests: HTML and assets
very very very very very fast
Can sit on each web server
Can be a load balancer
Saint and grace modes
http://www.mugo.ca
6. Varnish: Why
Traffic spikes!
vs more hardware
Cost
Reliance on NFS
vs CDN
Cost
Closer to the application, more hands on
Not closer to the user
Use together
http://www.mugo.ca
8. Varnish + eZ Publish
eZ Market extension
http://ez.no/Products/eZ-Market
Mugo Varnish extension:
https://github.com/mugoweb/mugo_varnish
http://www.mugo.ca
9. How to integrate
Custom static cache handler
https://github.com/ezsystems/ezpublish/pull/119
eZ Publish 2011.9 or 4.7
ezpEvent since 4.5
Purge specific URLs in Administration Interface
http://www.mugo.ca
10. Configuring Varnish
VCL
Similar to C
vcl_recv: what to do with the request
vcl_hit / vcl_miss
vcl_fetch: what to do with the response
vcl_deliver: send the response back
TTL
http://www.mugo.ca
11. vcl_recv: purge
if( req.request == "PURGE" )
{
# Limit access for security reasons
if( !client.ip ~ purge )
{
error 405 "Not allowed.";
}
# URL purges -- one for the URL and one for all view parameter variations
if( req.http.X-Purge-Url )
{
set req.http.X-Purge-Url1 = "^" + req.http.X-Purge-Url + "$";
set req.http.X-Purge-Url2 = "^" + req.http.X-Purge-Url + "/(";
ban( "obj.http.x-url ~ " + req.http.X-Purge-Url1 );
ban( "obj.http.x-url ~ " + req.http.X-Purge-Url2 );
error 200 "URL Purged.";
}
# Any regular expressions here
if( req.http.X-Purge-Reg )
{
ban( "obj.http.x-url ~ " + req.http.X-Purge-Reg );
error 200 "Regular Expression Purged.";
}
error 405 "Missing X-Purge-Url or X-Purge-Reg header.";
}
http://www.mugo.ca
12. vcl_fetch: setting TTL
# Only cache www.yoursite.com
# Only 200 responses
if( req.http.host == "www.yoursite.com" &&
beresp.status == 200
)
{
if( req.url ~ "^/var/plain/storage/images/.*" )
{
set beresp.ttl = 30d;
set beresp.http.X-Ttl = "30d";
}
else
{
# Default caching time
set beresp.ttl = 300s;
set beresp.http.X-Ttl = "300s";
}
}
http://www.mugo.ca
13. vcl_deliver: adding diagnostic info
set resp.http.X-Served-By = server.hostname;
if (obj.hits > 0)
{
set resp.http.X-Cache = "HIT";
set resp.http.X-Cache-Hits = obj.hits;
}
else
{
set resp.http.X-Cache = "MISS";
}
http://www.mugo.ca
14. Tweaks
Cookies: eZ Publish < 4.4
Controlling TTL and excluding pages
header( 'Edge-control: cache-maxage=86400s' );
{ezpagedata_append( 'http_headers', 'Edge-
Control: cache-maxage=0s' )}
Edge Side Includes
http://www.mugo.ca
15. Ongoing maintenance
varnishstat
varnishadm
curl -I http://www.yoursite.com
HTTP/1.1 200 OK
Server: Apache
X-Cache-Hits: 17
X-Cache: HIT
X-Served-By: CloudWeb2
Via: 1.1 varnish
X-Ttl: 300s
X-Powered-By: eZ Publish
Age: 206
http://www.mugo.ca
