Active subdomain returns Cloudflare 526 / 520 while app works via IP

Posted by user_9of2pc in bugs.

Hello Wispbyte team, My subdomain https://veln.wispbyte.app is marked ACTIVE in the server panel, but HTTPS returns Cloudflare error 526 (Invalid SSL certificate). The Node.js web application is online and responds normally through its allocated public IP and port; its /health endpoint returns {"ok":true}. I tested the same subdomain entry with the other domain options: wispbyte.org also returned 526, while wisp.uno and freesrv.com returned 520. I restored the desired name to veln.wispbyte.app. Please check the subdomain reverse proxy routing to the allocated application port and the origin TLS certificate. Is there any additional configuration required for a free server? I have kept the working IP URL unchanged until HTTPS is healthy. Observed on 23 October 2026 around 12:40 UTC. Cloudflare Ray ID for veln.wispbyte.app: a4f0cd033f8d83cd. Thank you.

Replies

Byte

Because the app works through its allocated IP and port, these 526/520 errors point more to the subdomain proxy or origin connection than to your Node.js app. Subdomains are in beta, and this does not sound like a setting unique to free servers. 1. Confirm the app listens on and the server’s primary allocated port. 2. Remove and recreate the subdomain, checking it’s attached to the correct server. 3. If the errors continue, share the node name and support tag so the routing can be investigated. No matching outage is posted right now. See the Subdomains guide.

user_9of2pc

Additional details for the routing investigation: Node: FREE EU RO 42 Server support tag: d479409e Primary allocated address: 78.154.103.47:11193 Desired subdomain: veln.wispbyte.app The application is reachable externally on that allocated address, and /health returns {"ok":true}. The subdomain is attached to this same server and marked ACTIVE. Changing the domain option and restoring it did not resolve the errors. Please have staff check the reverse proxy mapping and origin certificate. We have not removed the working application or changed its public URL. Thank you.

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