Connecting a raspberry to an Erlang cluster fails, incompatible OTP versions?

Hi all,
i want to connect a Raspberry to an Erlang cluster. I use full names, same cookies, the machines can ping each other (same LAN) and no firewall is in the way. Still, no luck, net_adm:ping ‘pangs’.
My app has been recompiled on the raspberry and seems to run fine (apart from the fact that it can’t connect).
The raspberry runs OTP 22 from the official Erlang site, the other nodes (a Ubuntu and a Win11) have a recent OTP25 and can connect to each other. Can the difference between the OTP versions be the reason? If not, any other hints? Are there any logs from epmd or the erlang runtime which can give some insight?


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Distribution compatibility is only guaranteed for 2 versions up (or down), so yes, 22 <-> 25 connections may not be possible. I’m not sure what is “OTP 22 from the official Erlang site” though.

You may also be running into this bug: Can't connect from 24 to 25 node when erl_epmd_port is used · Issue #6595 · erlang/otp · GitHub is you’re using EPMD-less installation.


Erlang and Elixir Packages Download - Erlang Solutions provides only OTP 22.1 for Raspbian, i’m not aware of a newer version and hesitate to compile it myself on such a small machine.
I will read the link the provided.


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I have built several versions on raspberries, via asdf.
It takes some time, but it works fine.

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Confirmed. OTP 22 cannot connect to OTP 25 and vice versa.

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I constantly rebuild releases on raspberry, asdf compiles without problems, but not quickly

so if new or even the newest version compile and work on Raspian, then i would kindly ask the maintainers to also provide a recent build on Erlang and Elixir Packages Download - Erlang Solutions