Switched one of our sites to CloudFlare DNS and in our code routines, we connect to the site via SSH by its domain as the host.
Apparently it kept timing out as we were connecting to the wrong IP resolved by CloudFlare DNS which wasn’t the real IP for our server at all.
So we had to switch to DNS Only at CloudFlare for the A record of the domain and everything is working correctly again.
It took us a while to figure it out. It’s a tricky one. 😉