running many `cluster join` in parallel fails randomly

[Marian Gasparovic]

We are now deploying Sunbeam with nine nodes which means running eight `cluster join` commands. Usually one of them fails immediately. When we switched to running three joins in parallel, problem disappeared.

2024-07-02-08:40:14 root ERROR [localhost] Command failed: ssh -o StrictHostKeyChecking=no -o UserKnownHostsFile=/dev/null solqa-lab1-server-16.nosilo.lab1.solutionsqa -- sunbeam cluster join --token eyJzZWNyZXQiOiI4YzkwYTAxOTMxM2U4MjE4NjNhYzM4MGQ5YmZiYTYwYjg5MWI0NTNhN2RmNzc5ZWY1MzY5OGExYjJkYzkxZjAxIiwiZmluZ2VycHJpbnQiOiIzMDNhYmMyNmU3M2NkYzZiNzdhYjNkYzQ3ZGI3YWViZmU1MWU1MDRmM2UwYTQwMTc0MTVmNTVkNWNmNGY0YTk3Iiwiam9pbl9hZGRyZXNzZXMiOlsiMTAuMjQ2LjE2NC4xNDg6NzAwMCJdfQ== --role storage
2024-07-02-08:40:14 root ERROR 1[localhost] STDOUT follows:
b''
2024-07-02-08:40:14 root ERROR 2[localhost] STDERR follows:
Warning: Permanently added 'solqa-lab1-server-16.nosilo.lab1.solutionsqa' (ED25519) to the list of known hosts.
Error: Juju not detected: please install snap

https://solutions.qa.canonical.com/testruns/f0cec44c-77fb-46ca-9411-7402a7472c7c

I am really not sure if calling many joins is the issue as the command fails immediately.
Maybe something to keep an eye on