Question

There are plenty of threads and documentation about parallel ssh, but I can’t find anything on passing custom parameters to each host. Using pssh as an example, the hosts file is defined as:

111.111.111.111
222.222.222.222

However, I want to pass custom parameters to each host via a shell script, like this:

111.111.111.111 param1a param1b ...
222.222.222.222 param2a param2b ...

Or, better, the hosts and parameters would be split between 2 files.

Because this isn’t common, is this misuse of parallel ssh? Should I just create many ssh processes from my script? How should I approach this?

Answer 1

You could use GNU parallel.

Suppose you have a file argfile:

111.111.111.111 param1a param1b ...
222.222.222.222 param2a param2b ...

Then running

parallel --colsep ' ' ssh {1} prog {2} {3} ... :::: argfile

Would run prog on each host with the corresponding parameters. It is important that the number of parameters be the same for each host.