Host key verification failed.

All,
In my search for CPU load distribution I wanted to give pool [1] a try.
However, I am unable to start slaves due to SSH issues. I'm currently using
a single box, but this shouldn't be an issue.

What I've done:

1. created a new private / public key pair:
-> id_crane_slave & id_crane_slave.pub

2. added the key to the agent:
$ ssh-add ~/.ssh/id_crane_slave

3. added the key to the authorized keys:
$ cat ~/.ssh/id_crane_slave.pub >> ~/.ssh/authorized_keys
$ chmod 600 ~/.ssh/authorized_keys

4. added the entry to /etc/hosts:
127.0.0.1 dev.local

Now I can login to self without the need for a password:

$ ssh [email protected]
Last login: Tue Jul 13 12:19:24 2021 from ::1
$

However I can't make it work with distributed Erlang:

$ erl -name [email protected]
Erlang/OTP 24 [erts-12.0.3] [source] [64-bit] [smp:8:8] [ds:8:8:10]
[async-threads:1] [jit]

Eshell V12.0.3  (abort with ^G)
([email protected])1> {ok, Node} = slave:start('dev.local', 'roberto').
Host key verification failed.

And the console hangs.

All works when I use short names:

$  erl -sname foo
Erlang/OTP 24 [erts-12.0.3] [source] [64-bit] [smp:8:8] [ds:8:8:10]
[async-threads:1] [jit]

Eshell V12.0.3  (abort with ^G)
(foo@rob)1> slave:start_link(rob, bar).
{ok,bar@rob}

Any kind soul with pointers would be welcome.

Best,
r.







[1] https://erlang.org/doc/man/pool.html