How Magento cache works with multiple Varnish instances

Magento supports multiple Varnish instances out of the box.

This topic shows the basics of configuring multiple Varnish instances with Magento.

Configuration to purge multiple Varnish instances

Magento purges Varnish hosts after you configure Varnish hosts using the magento setup:config:set command.

You should use the --http-cache-hosts parameter to specify a comma-separated list of Varnish hosts and listen ports. (Do not separate hosts with a space character.)

The parameter format must be <hostname or ip>:<listen port>, where you can omit <listen port> if it’s port 80.

For example,

magento setup:config:set --http-cache-hosts=192.0.2.100,192.0.2.155:6081

You can then purge all Varnish hosts when you refresh the Magento cache (also referred to as cleaning the cache) in the Magento Admin or using the command line.

To refresh the cache using the Admin, click SYSTEM > Tools > Cache Management, then click Flush Magento Cache at the top of the page. (You can also refresh individual cache types.)

To refresh the cache of multiple Varnish instances from cli use the magento cache:clean [type] command as the Magento file system owner.