Custom Domains setup success, but the cloudflare cannot access the origin server

Question

I setup the custom domain successfully, the cname record was added successfully, with the proxy closed. But when I use my custom domain to access the app, cloudflare reports that the SSL handshake with the origin server fails (525) as this snapshot shows:

Troubleshooting information from cloudflare: https://developers.cloudflare.com/support/troubleshooting/http-status-codes/cloudflare-5xx-errors/error-525/
I think the issue lies in the proxy in claw cloud run. After my custom doamin config was applied, the origin server becomes inaccessible because of the failure in the connection:

Is there anyone who has any insights? Please advise!

qingyou · Answer

I'm the same, have you solved it yet?

单徐浩启 · Answer

Where did you buy your domain name?
It's possible that there is a problem with your domain hosted on CloudFlare. I've never had this happen to me.

RK · Answer

This happened to me as well. Here's what worked in my case:

Make sure the CNAME record is set to "DNS Only" (grey cloud) in Cloudflare, not proxied (orange cloud).
Wait a few hours — for me, it took around 4 hours before the DNS change fully propagated and the SSL handshake started working.
During this waiting period, try accessing the app from a different network or browser. Sometimes cached SSL info can cause the same issue to appear even after things are fixed.

Once the DNS settled and everything started working smoothly.

Custom Domains setup success, but the cloudflare cannot access the origin server

3 Answers