Magento with Varnish - var/cache folder still being used

Question

I have a Magento store configured with Varnish. When everything is up to date site is fast. If I change something in the backend it doesn't get reflected on frontend unless I manually delete var/cache/mage--* folders.

By the looks of the documentation, this folder should be empty after I configured Varnish.

How do I debug this?

Answer 1

You can check your Varnish configuration with n98-magerun2

Use the command

n98-magerun2.phar config:show | grep full_page_cache

You should see something like the following where magento2_php-apache_1 is the hostname of your Magento 2 server and backend_port is the tcp port of the content (magento 2) server

system/full_page_cache/caching_application - 2
system/full_page_cache/varnish/access_list - magento2_php-apache_1
system/full_page_cache/varnish/backend_host - magento2_php-apache_1
system/full_page_cache/varnish/backend_port - 8080
system/full_page_cache/varnish/grace_period - 300

You should also confirm your env.php is configured with an http_cache_host

'http_cache_hosts' => [
    [
        'host' => 'varnish',
        'port' => '6081'
    ]
],

The port here is the port Magento uses to communicate with the varnish server. You can also set this configuration with

magento setup:config:set --http-cache-hosts=127.0.0.1:6081

The varnish vcl should also be configured correctly with the port of your content (magento) server

# Default backend definition. Set this to point to your content server.
backend default {
.host = "127.0.0.1";
.port = "8080";
}

Don’t get the ports mixed up :

• By default Varnish is configured to listen for incoming external client http requests on TCP 6081.
• The backend_port configured in admin is only used for the vcl config generation.
• The env.php http_cache_hosts port is the port used to communicate with varnish.