How To Run Multiple SSH Command On Remote Machine And Exit Safely

ssh root@server2 "sync; sync; /sbin/shutdown -h now"

Tutorial details Difficulty Easy (rss) Root privileges No Requirements bash+ssh Time 2m

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Simple bash syntax to run multiple commands on remote machine

I have a backup sync program on local server. I have an ssh password less login set up, and I can run commands on an external server in bash script doing:How do I run multiple commands in bash on a remote Unix or Linux server? What is the best way to SSH in and run various unix commands in a bash shell?[donotprint][/donotprint]There are various ways to run multiple commands on a remote Unix server. This page show the easiest way to ssh and run multiple commands in using bash shell. The syntax is as follows.

Simply run command2 if command1 successful on a remote host called foo:

$ ssh bar@foo "command1 && command2"

For example, run uptime and date commands on a box named ‘centos7’ as ‘vivek’ user::

ssh vivek@centos7 "uptime && date"

Sample outputs:

18 : 36 : 17 up 1 day, 8 : 14 , 0 users, load average: 1.02 , 1.06 , 1.05 Fri Jun 7 18 : 36 : 17 IST 2019 18:36:17 up 1 day, 8:14, 0 users, load average: 1.02, 1.06, 1.05 Fri Jun 7 18:36:17 IST 2019

How To Run Multiple SSH Command

Run date and hostname commands:

$ ssh user@host "date && hostname"

You can run sudo command as follows on a remote box called server1.cyberciti.biz:

$ ssh -t vivek@server1.cyberciti.biz "sudo /sbin/shutdown -h now"

And, finally:

$ ssh root@server1.cyberciti.biz "sync && sync && /sbin/shutdown -h now"



Bash here document syntax to run multiple SSH command

The here document syntax tells the shell to read input from the current source (HERE) until a line containing only word (HERE) is seen:

ssh server1 << HERE command1 command2 HERE ssh server1 << HERE command1 command2 HERE

Here is another example to run a multiple commands on a remote system:

ssh vivek @ server1.cyberciti.biz << EOF date hostname cat /etc/resolv.conf EOF ssh vivek@server1.cyberciti.biz << EOF date hostname cat /etc/resolv.conf EOF

With sudo command type:

ssh -t vivek @ server1.cyberciti.biz << EOF sync sync sudo /sbin/shutdown -h 0 EOF ssh -t vivek@server1.cyberciti.biz << EOF sync sync sudo /sbin/shutdown -h 0 EOF

Pipe script to a remote server

Finally, create a script called “remote-box-commands.bash” as follows on your local server:

date hostname cat / etc / resolv.conf date hostname cat /etc/resolv.conf

Run it as follows on a remote server called nas02nixcrafthomeserver:

$ cat remote-box-commands.bash | ssh user@nas02nixcrafthomeserver

OR

cat remote-box-commands.bash | ssh -t vivek@nas02nixcrafthomeserver

How to ssh to multiple servers and run commands

One can use simple bash for loop as follows. In this example, run uptime command on three Linux server named box1, box2, and box3:

for s in box1 box2 box3 do ssh vivek @ ${s} uptime done for s in box1 box2 box3 do ssh vivek@${s} uptime done

Running local bash script on remote system

Create a shell script as follows:

#!/bin/bash # Name: test.sh # Purpose: Run multiple commands on a remote box # ---------------------------------------------------- uptime date whoami #!/bin/bash # Name: test.sh # Purpose: Run multiple commands on a remote box # ---------------------------------------------------- uptime date whoami

Now run it as follows on host named server1.cyberciti.biz:

ssh vivek@server1.cyberciti.biz 'bash -s' < /path/to/test.sh

OR run it on four servers:

for s in server { 1 .. 4 } .cyberciti.biz do ssh vivek @ ${s} 'bash -s' < / home / vivek / bin / test.sh done for s in server{1..4}.cyberciti.biz do ssh vivek@${s} 'bash -s' < /home/vivek/bin/test.sh done

Please note that the -t option will get rid of "Sorry, you must have a tty to run sudo/insert your-command-here" error message. You can also use pssh (parallel ssh) for executing ssh in parallel on a number of Linux/Unix/BSD servers. For more info see your ssh and bash command man page:

$ man ssh

$ man bash

$ man sudo

And there you have it, multiple bash shell command run using nothing but ssh client/sever model. A better option is to use the ansible tool.