I'm doing my first Slurm install from scratch on a 2-node Ubuntu cluster (1 head, 1 worker)
I followed those instructions for Munge installation (here and here, pretty similar) ; munge is active on each node but when I do the recommended test munge -n | ssh <remote node> unmunge I get a Permission denied (publickey).
Why am I seeing this? Before installing munge, is there a requirement that the munge user or some other user should be able to SSH to the other node from both nodes? How to fix this problem?
SSH is installed on both nodes, and the same munge.key is present at /etc/munge on both nodes