UDP isn't working

This was working with roughly the same configuration earlier: binding to fly-global-service, using the same port inside and outside. I meticulously followed the docs. I can’t figure out what’s happening here.

All connections to the service time out. The app itself doesn’t see any udp messages. Can anyone help me out?

I remember reading in the docs that a dedicated IP is needed for this. Can you give this a shot?

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Does it need a dedicated IP? That doubles the cost of a small vm, with ipv6 udp support still missing. An official answer would be appreciated if that’s the case.

Unsure but this seems to imply that. Would be good for an official confirmation.

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It does require a dedicated IP.

The cost is per app, but yes if you only have 1 VM then it doubles it price.

Ah thanks! It would really be cool if you could clarify that in your documentation (ex: the udp page, caveats, where it mentions ipv6 but nothing about shared ipv4)… but I won’t hold my breath. I assume this is expected fallout of the move to paid dedicated ipv4 addresses.

It’s a documentation change we overlooked for sure, but basically shared IPv4 only works for TCP [+TLS] + HTTP on standard ports (443 w/ tls and 80 for http-only).

Right, it’s an “ip address” where you can’t actually use IP protocols. It’s virtual hosts called by another name so nobody realizes Fly’s pivoting into a virtual hosting company.

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