[erlang-questions] remsh failing silently

[Ben Hood]

Hi,

I'm failing to invoke remsh on an OTP 17.5.6.10 build (cross compiled
for ppc64).

Kicking off the first node:

$ erl -sname a -setcookie 1
Eshell V6.4.1.7  (abort with ^G)
(a@REDACTED)1>

I try to connect to it from a second node (to no avail):

$ erl -sname b -remsh a@REDACTED -setcookie 1
Eshell V6.4.1.7  (abort with ^G)
(b@REDACTED)1> nodes().
[]
(b@REDACTED)2>

The port mapper indicates that both nodes registered with it:

$ epmd -names
epmd: up and running on port 4369 with data:
name a at port 46201
name b at port 35447

However, if I actively ping the the first node from the second, the
ping succeeds and I assume that the net_kernel subsystem has joined
the nodes:

(b@REDACTED)2> net_adm:ping('a@REDACTED').
pong
(b@REDACTED)3> nodes().
[a@REDACTED]
(b@REDACTED)4>

So I'm left wondering why the remsh argument can't trigger the same
node join when the second Erlang process is started.

The same invocation works perfectly well on more up to date versions
of OTP, but I'm prevented from just doing a large version upgrade.

Is there some way to get the runtime to output verbose diagnostics to
try to debug this?

TIA,

Ben