Struggling with Private Networking

Questions / Help
1

I’ve deployed 2 apps to fly.io:

  • A database I don’t want accessible to the internet
  • An oauth2-proxy that should front traffic to the database

Sadly, while I can ping and dig any of the private _apps.internal or <app>.internal addresses successfully, I’m unable to connect directly to my database at <db app>.internal. Should I be using the internal port of the container running the database? Any pointers about sending tcp packets between separate apps in the same org would be much appreciated. Thanks!

2

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

3

Groan — yes! I’m fairly certain your first point is the issue. I listened on 0.0.0.0, which is only ipv4. Thank you for these links!!

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