I have several different domains/sites experiencing the same anomaly.
While in Wordpress Admin dashboard - clicking to open various links/features… I randomly get 520 errors. These are instantaneous - and result in no errors in server or WP logs. The page recovers upon reload. (ie not a server error per se)
This has happened well over 100 times, and I have spent about 20 hours trying to figure it out.
I am quite certain it has something to do with CACHING… specifically WP Super Cache. Absolutely 100% related to Cloudflare being enabled. With caching disabled I don’t seem to see the problem.
I have no clue how to narrow down the trouble-shooting or to resolve why/how this is occurring. Please do not suggest some generic trouble-shooting article not specific to this. I have read them all.
WP Super Cache plugin has no support.
Cloudflare support forms have errors that didn’t allow submission.
May I ask what is your domain name and who is your hosting provider, if so?
Maybe some recent and planned maintenance period at the DC from your hosting provider?
Before moving to Cloudflare, was your Website working over HTTPS connection?
If so, did you had an valid SSL certificate installed at your origin host / server which covers both your naked (root) domain any any other needed sub-domain like www, mail, etc.?
May I ask what SSL option have you got selected under the SSL/TLS tab at Cloudflare dashboard for your domain ( Flexible, Full, Full Strict … )?
Here is a way to re-check if you correctly setup the SSL for your domain with Cloudflare:
Regarding available SSL options at Cloudflare dashboard, check here:
If any other issues appear, follow the needed steps for troubleshooting from article below:
In case you do not have an SSL certificate, you can use Cloudflare SSL, if so, kindly make sure you follow the instructions as follows on the below article to setup an SSL certificate using Cloudflare CA Origin Certificate: