On this page
Varnish as HTTP Cache
Varnish is a HTTP proxy-cache, which works as a reverse proxy between your application and the client. Following rules defined by the user, Varnish will cache the data of an application to reduce the load on its server. We use Varnish 6.6.0 and varnish-modules 0.18.0.
Varnish is only available on PHP, Go and Node.js applications. Support for other applications is in discussion.
For more information about it, contact us at [email protected].
Enable Varnish for your application
To enable it, you just have to create a
varnish.vcl file in the
This file describes how Varnish caches your applications and how it decides to return a cached resource or not.
vcl 4.1;and backend section of the
varnish.vclconfiguration file are not necessary as they are already handled by Clever Cloud. If you have a PHP FTP application or if your
varnish.vclfile is on an FS Bucket, make sure you redeploy the application for the changes to take effect.
To know how to write your
varnish.vcl file, please have a look at the Varnish 6 book.
Listen on the right port
Once varnish is enabled, your application should no longer listen on port 8080, but on port 8081. Because it’s Varnish that will listen on port 8080, and it will have in its configuration your application as backend.
Configure the cache size
You can change the storage size specified in the varnish.params file with the
CC_VARNISH_STORAGE_SIZE environment variable (the default value is
Varnish 6 migration
If you already have a configuration for an older version of varnish, you can read this guide to upgrade to version 6.
We provide some examples of Varnish configuration files that you can
use for your application. Create a
/clevercloud folder at the root of your application if it does not exist,
rename the file to
varnish.vcl and move it in the