[erlang-bugs] Cannot bind epmd to an IPv4 address after building with -DEPMD6

[Dariusz Gadomski]

On Fri, Nov 14, 2014 at 11:01:22AM +0100, Dariusz Gadomski wrote:
> Hello everyone,
> 
> There are users observing problems with binding to an IPv4 address with
> erlang 16b3 version built with -DEPMD6 flag [1]. This flag has been added
> as a response to another bug [2].
> 
> By looking at erts/epmd/src/epmd_int.h I see that the address definitions are
> mutually exclusive - enabling IPv6 makes all addresses IPv6-only which may
> result in problems with binding to a specific IPv4 address:
> $ ERL_EPMD_ADDRESS="127.0.0.1" epmd
> epmd: Fri Nov 14 11:00:47 2014: cannot parse IP address "127.0.0.1"
> 
> Can you please confirm this? Is it a known issue? Maybe there is a workaround?
> 
> [1] https://bugs.launchpad.net/ubuntu/+source/erlang/+bug/1374109
> [2] https://bugs.launchpad.net/ubuntu/+source/rabbitmq-server/+bug/1312507

Hello again,

I have made an interesting observation. There is a change linked from
[3] on github [4]. This change adds support for IPv6 node registration to
epmd.

As a side effect it fixes the original issue I mentioned above. Is
anyone aware if there are any plans of merging it to the main
codebase?

[3] http://www.erlang.org/development/
[4] https://github.com/msantos/otp/compare/erlang:maint...epmd-IPv6-node-reg

Thanks!
Dariusz Gadomski