How can I automate running commands remotely over SSH to multiple servers in parallel?

Question

I\'ve searched around a bit for similar questions, but other than running one command or perhaps a few command with items such as:

ssh user@host -t sudo su -         


        

Answer 1

Creates hostname ssh command of all machines accessed. by Quierati http://pastebin.com/pddEQWq2

#Use in .bashrc
#Use "HashKnownHosts no" in ~/.ssh/config or /etc/ssh/ssh_config 
# If known_hosts is encrypted and delete known_hosts

[ ! -d ~/bin ] && mkdir ~/bin
for host in `cut -d, -f1 ~/.ssh/known_hosts|cut -f1 -d " "`;
  do
    [ ! -s ~/bin/$host ] && echo ssh $host '$*' > ~/bin/$host
done
[ -d ~/bin ] && chmod -R 700 ~/bin
export PATH=$PATH:~/bin 

Ex Execute:

$for i in hostname{1..10}; do $i who;done