Currently a munge key can be specified using openhpc_munge_key_path. Having the munge key around on the deploy host isn't ideal and isn't compatible with the slurm appliance which expects to be able to set the munge key content directly via a variable. This PR changes to the latter approach as it seems better.
This is slightly tricky to get right as:
We must support no munge key being provided, but that has to be idempotent (so no use generating a munge key on each run - luckily the slurm package installs actually generate one)
We have to give an (eventually) consistent munge key across the cluster for three situations:
Entire cluster in play
Only control node in play
Only compute node(s) in play (used for packer build in slurm appliance)
Currently a munge key can be specified using
openhpc_munge_key_path. Having the munge key around on the deploy host isn't ideal and isn't compatible with the slurm appliance which expects to be able to set the munge key content directly via a variable. This PR changes to the latter approach as it seems better.This is slightly tricky to get right as:
Note first two commits have a wider application.