@alpha and possibly @postmodern I used to use Capistrano to have a REPL where I could run commands on a bunch of different machines, essentially doing a filter then .each{} to return the results to an array. I need to perform the same thing at work, so Ronin is out (classed as an attack tool by security). Is Capistrano still popular for something like this? Have an alternative you like better?

@kfm @postmodern I have used tmux to do this in the past 🙈

@kfm @alpha you could do this with net-ssh, which Capistrano uses.
https://github.com/net-ssh/net-ssh

You'd need to execute each separate SSH session in a separate thread or Async fiber. There apparently was a net-ssh-multi gem, but it looks defunct.

@alpha @kfm looks like there's several tools for doing multiple parallel SSH sessions:

https://github.com/robinbowes/pssh
https://github.com/grondo/pdsh
https://github.com/duncs/clusterssh
https://clusterit.sourceforge.net/
https://sourceforge.net/projects/mussh/
https://unix.stackexchange.com/questions/19008/automatically-run-commands-over-ssh-on-many-servers/704487#704487