Install pssh on ubuntu
Open the terminal and run the following commands
sudo apt-get install python-pip
sudo pip install pssh
pssh [-vAiIP] [-h hosts_file] [-H [user@]host[:port]] [-l user] [-p par] [-o outdir] [-e errdir] [-t timeout] [-O options] [-x args] [-X arg] command
Connect to host1 and host2, and print "hello, world" from each
pssh -i -H "host1 host2" echo "hello, world"
Print "hello, world" from each host specified in the file hosts.txt
pssh -i -h hosts.txt echo "hello, world"
Run a command as root with a prompt for the root password
pssh -i -h hosts.txt -A -l root echo hi
Run a long command without timing out
pssh -i -h hosts.txt -t 0 sleep 10000
If the file hosts.txt has a large number of entries, say 100, then the parallelism option may also be set to 100 to ensure that the commands are run concurrently
pssh -i -h hosts.txt -p 100 -t 0 sleep 10000
Run a command without checking or saving host keys
pssh -i -H host1 -H host2 -x "-O StrictHostKeyChecking=no -O UserKnownHostsFile=/dev/null -O GlobalKnownHostsFile=/dev/null" echo hi
Print the node number for each connection (this will print 0, 1, and 2)
pssh -i -H host1 -H host1 -H host2 ‘echo $PSSH_NODENUM'
The above examples from PSSH man page
If you have a set of hosts that you connect to frequently with specific options, it may be helpful to create an alias such as:
alias pssh_servers="pssh -h /path/to/server_list.txt -l root -A"
The ssh_config file can include an arbitrary number of Host sections. Each host entry specifies ssh options which apply only to the given host. Host definitions can even behave like aliases if the HostName option is included. This ssh feature, in combination with pssh host files, provides a tremendous amount of flexibility.