Magento 2.3.3 Varnish Cache invalidating and auto purging every 10 minutes

Question

I have just implemented Varnish 6.0 on our Magento 2.3.3 install, everything seems to be working fine except our Magento cache/varnish cache is being flushed by Magento every 10 minutes.

I can see cache a lot of caches invalidate entires in debug.log. Obviously this is no good for Varnish implementation with it being purged every 10 minutes. I have disconnected the purge connection between Magento and Varnish via env.php now we have Varnish caching long and not being purged by Magento every 10 minutes but no option to manually purge through Magento admin.

We have a few third-party extensions installed but debug.log does not give us any indication as to which module is triggering the invalidation.

Does anyone have any similar experience or know where to start debugging this issue?

Thanks

Answer 1

Unfortunately changes in product data to configuration changes to automated processes such as currency updates will invalidate cache.

We had this on a magento 1 store and sounds like pretty much the same scenario in magento 2.

My best advice is create a console command which curls varnish via php

curl -X PURGE http://example.com/url1

I believe if you do root url it will purge entire cache

You could build on this by putting a form somewhere in the admin which let's you/user purge urls

Answer 2

I have resolved the above issue. It was due to Magento Google Shopping Ads extension. The website verification part of the setup was left incomplete. So it appears the extension was running cron tasks every 10 minutes to verify/establish connection to Google. This cron task must have included cache invalidation.