Could not resolve host for remote upload
Remote URL upload checks the hostname before downloading. If DNS lookup fails (or returns nothing), you get this error.
Why this happens
The server runs dns.lookup on the URL host. NXDOMAIN, timeout, or empty results become Could not resolve host for remote upload. This is separate from “private IP blocked” or “IPv6-only host” messages.
Also confirm Remote URL upload is allowed for the plan and the site mod is on.
Diagnose and fix
1. Open the URL in a browser — does the hostname work?
2. From the app server: dig +short example.com or getent hosts example.com. Fix DNS (/etc/resolv.conf, firewall to resolvers) if the VPS cannot resolve public names.
3. Typos in the pasted URL (spaces, missing scheme). Use https://….
4. Users & limits — Remote URL not blocked for that tier; Settings → Mods → Remote URL upload on.
5. If the host resolves only to IPv6, you may see a different message (“no IPv4 address”) — remote upload currently requires a public IPv4 target.