Recently I come across a nice little nifty tool called pssh to run a single command on multiple Linux / UNIX / BSD servers. You can easily increase your productivy with this SSH tool.
More about pssh
pssh is a command line tool for executing ssh in parallel on some hosts. It specialties includes:
- Sending input to all of the processes
- Inputting a password to ssh
- Saving output to files
- IT/sysadmin taks automation such as patching servers
- Timing out and more
Let us see how to install and use pssh on Linux and Unix-like system.
Installation
You can install pssh as per your Linux and Unix variant. Once package installed, you can get parallel versions of the openssh tools. Included in the installation:
- Parallel ssh (pssh command)
- Parallel scp (pscp command )
- Parallel rsync (prsync command)
- Parallel nuke (pnuke command)
- Parallel slurp (pslurp command)
Install pssh on Debian/Ubuntu Linux
Type the following apt-get command/apt command to install pssh:
$ sudo apt install pssh
OR
$ sudo apt-get install pssh
Sample outputs:
Install pssh on Apple MacOS X
Type the following brew command:
$ brew install pssh
Sample outputs:
Install pssh on FreeBSD unix
Type any one of the command:
# cd /usr/ports/security/pssh/ && make install clean
OR
# pkg install pssh
Sample outputs:
Install pssh on RHEL/CentOS/Fedora Linux
First turn on EPEL repo and type the following command yum command:
$ sudo yum install pssh
Sample outputs:
Install pssh on Fedora Linux
Type the following dnf command:
$ sudo dnf install pssh
Sample outputs:
Install pssh on Arch Linux
Type the following command:
$ sudo pacman -S python-pip
$ pip install pssh
How to use pssh command
First you need to create a text file called hosts file from which pssh read hosts names. The syntax is pretty simple. Each line in the host file are of the form [user@]host[:port] and can include blank lines and comments lines beginning with “#”. Here is my sample file named ~/.pssh_hosts_files:
$ cat ~/.pssh_hosts_files
vivek@dellm6700
root@192.168.2.30
root@192.168.2.45
root@192.168.2.46
Run the date command all hosts:
$ pssh -i -h ~/.pssh_hosts_files date
Sample outputs:
[1] 18:10:10 [SUCCESS] root@192.168.2.46 Sun Feb 26 18:10:10 IST 2017 [2] 18:10:10 [SUCCESS] vivek@dellm6700 Sun Feb 26 18:10:10 IST 2017 [3] 18:10:10 [SUCCESS] root@192.168.2.45 Sun Feb 26 18:10:10 IST 2017 [4] 18:10:10 [SUCCESS] root@192.168.2.30 Sun Feb 26 18:10:10 IST 2017
Run the uptime command on each host:
$ pssh -i -h ~/.pssh_hosts_files uptime
Sample outputs:
[1] 18:11:15 [SUCCESS] root@192.168.2.45 18:11:15 up 2:29, 0 users, load average: 0.00, 0.00, 0.00 [2] 18:11:15 [SUCCESS] vivek@dellm6700 18:11:15 up 19:06, 0 users, load average: 0.13, 0.25, 0.27 [3] 18:11:15 [SUCCESS] root@192.168.2.46 18:11:15 up 1:55, 0 users, load average: 0.00, 0.00, 0.00 [4] 18:11:15 [SUCCESS] root@192.168.2.30 6:11PM up 1 day, 21:38, 0 users, load averages: 0.12, 0.14, 0.09
You can now automate common sysadmin tasks such as patching all servers:
$ pssh -h ~/.pssh_hosts_files -- sudo yum -y update
OR
$ pssh -h ~/.pssh_hosts_files -- sudo apt-get -y update
$ pssh -h ~/.pssh_hosts_files -- sudo apt-get -y upgrade
How do I use pssh to copy file to all servers?
The syntax is:
pscp -h ~/.pssh_hosts_files src dest
To copy $HOME/demo.txt to /tmp/ on all servers, enter:
$ pscp -h ~/.pssh_hosts_files $HOME/demo.txt /tmp/
Sample outputs:
[1] 18:17:35 [SUCCESS] vivek@dellm6700 [2] 18:17:35 [SUCCESS] root@192.168.2.45 [3] 18:17:35 [SUCCESS] root@192.168.2.46 [4] 18:17:35 [SUCCESS] root@192.168.2.30
Or use the prsync command for efficient copying of files:
$ prsync -h ~/.pssh_hosts_files /etc/passwd /tmp/
$ prsync -h ~/.pssh_hosts_files *.html /var/www/html/
How do I kill processes in parallel on a number of hosts?
Use the pnuke command for killing processes in parallel on a number of hosts. The syntax is:
$ pnuke -h .pssh_hosts_files process_name
### kill nginx and firefox on hosts:
$ pnuke -h ~/.pssh_hosts_files firefox
$ pnuke -h ~/.pssh_hosts_files nginx
See pssh/pscp command man pages for more information.
Conclusion
pssh is a pretty good tool for parallel SSH command execution on many servers. It quite is useful if you have 5 or 10 servers. Nevertheless, if you need to do something complicated you should look into Ansible and co.
5 comment
from "violent python" #!./env/bin/python """ SSH Botnet This script logs into several different machines with ssh and sends commands to each of them in tandem Don't be a moron, please don't use this for something illegal. Usage: ssh_botnet.py ssh_botnet.py (-h | --help) ssh_botnet.py (-v | --version) Options: -h --help Show this screen. --version Show version """ import pxssh from docopt import docopt from colorama import Fore, init class Client: def __init__(self, host, user, password): self.host = host self.user = user self.password = password self.session = self.connect() def connect(self): try: ssh = pxssh.pxssh() ssh.login(self.host, self.user, self.password) return ssh except Exception, e: print Fore.RED + '[-] Error Connecting' + Fore.RESET print e def send_command(self, cmd): self.session.sendline(cmd) self.session.prompt() return self.session.before def botnet_command(command, botnet): for client in botnet: output = client.send_command(command) print Fore.GREEN + '[*] Output from ' + client.host + Fore.RESET print '[+] ' + output + '\n' def add_client(host, user, password, botnet): client = Client(host, user, password) botnet.append(client) def main(): botnet = [] add_client('10.10.10.110', 'root', 'toor', botnet) add_client('10.10.10.120', 'root', 'toor', botnet) add_client('10.10.10.130', 'root', 'toor', botnet) botnet_command('uname -v', botnet) if __name__ == '__main__': init() docopt(__doc__, version=0.1) main()Pssh is ok, but I prefer mpssh. I can define groups of hosts and call by name.
Neat utility ! I have used a similar utility in the past, called pdsh.
Not sure about other flavours, but apt installs the parallel-ssh binary and not pssh – one can always create a link, though
Thanks !
I rather use Ansible – the simplest way to automate apps and IT infrastructure :)
@nobody
Was actually going to mention ansible too