On Sat, 4 Mar 2017 09:41:31 -0500
ssh user1@ipaddress command & (assuming that the
'&' runs the local
ssh in the background -- it doesn't!)
I have no idea how it could fail to run it in the background,
unless perhaps it is stopping because it is asking for tty input.
You can fix that with the -n option and/or -f options.
Or perhaps it is asking for credentials. You can fix that with public
keys and an ssh-agent so it doesn't have to ask.