Purge the Varnish FPC
The Stratus CLI is the best way to clear Varnish through shell on Stratus.
Curl still works if you are using SSH, the difference is the Varnish hostname is varnish
curl -X 'PURGE' -H'X-Magento-Tags-Pattern: .*' varnish
Magento 2 users should set their http-cache-host accordingly:
php bin/magento setup:config:set --http-cache-hosts=varnish
If the above is set you can perform a typical cache clear via the Magento 2 admin or Magento commands
php bin/magento cache:clean
You can also purge Varnish via the Flush Cache button under the Varnish->Info menu in the stratus panel.
Purging one URL
You have the option to purge just one url in Varnish cache under Varnish->Url Cache. Choose the correct base url, paste in the url and click "clear cache".
Static files not refreshing
Magento 2 currently has a bug in its VCL: where static files will not refresh despite the purge listed above. See https://github.com/magento/magento2/issues/8113
As a workaround, you can run this command via the shell on your MageMojo server –
varnishadm "ban req.url ~ "/" "
For more understanding about Magento 2 and Varnish, please read the official dev docs at http://devdocs.magento.com/guides/v2.0/config-guide/varnish/use-varnish-cache.html