Is the database listening on all network interfaces? Specifically, is it listening on IPv6? Not doing so is, by far, the most common pitfall: Cannot Connect to Machines on internal Service Port - #3 by ignoramous
For pointers on 6pn, check out test apps by Fly engs: Fly io Newbie: Making internal requests between apps - #3 by ignoramous
If you’re using Fly Machines, then you’d need to assign a Flycast 6pn IP (free to use) to wake 'em up: Cloning a stopped machine? - #5 by ignoramous
See also: Specify instance-id in fly-replay header - #10 by ignoramous