After updating my Discourse site to 3.5.0.beta8-dev, I’m suddenly getting a 521 “Web server is down” error when accessing the site through Cloudflare. This is unexpected since I had previously configured it according to this guide, and it had been working perfectly until now.
Then I tried changing the SSL/TLS encryption mode in Cloudflare from Full (Strict) to Flexible, and the site loaded again.
Does anyone know why this might be happening after the update?
Is there something new in 3.5.0.beta8-dev that could affect Cloudflare compatibility or HTTPS handling?
Any help or suggestions would be greatly appreciated!
Working from memory, cloudflare certs have a 90 day duration. This will require you to create new certs every 3 months. Do you remember how old your certs are?
The default setting is to use Let’s Encrypt. The system will auto renew your certs for you. One less thing to manage manually.