How do I find the exit status of a remote command executed via ssh?

by on February 5, 2006 · 10 comments· LAST UPDATED February 5, 2006

in

After writing about "Execute Commands on Multiple Linux or UNIX Servers", I received couple of emails asking about "how to find out the exit status of a remote command executed via ssh command." Well I never ever used exit status of a remote command executed via ssh. However, here is simple way to find out exit status:

$ ssh user@ras.nixcraft.in date;echo $?

Sun Feb  5 19:01:01 IST 2006
0

First line is nothing but output of date command, zero (0) is exit status of date command. Try another command

$ ssh user@ras.nixcraft.in today;echo $?

bash: today: command not found
127

Please note that ssh exits with the exit status of the remote command or with 255 if an error occurred. For example:

$ ssh user@ras.nixcraft.in today
$ echo $?

bash: today: command not found
127

Since today is not a valid command bash exited with 127 exit code. However, you cannot use conditional control operator:

  • && : Execute command only if command returns an exit status of zero
  • || : Execute command only if command returns an exit status of non zero

So following command will never display Command failed message:

$ ssh root@192.168.1.16 today;echo $? || echo "Command failed"

What you can do is create a shell script wrapper that will execute a remote command and returns the status locally. So if you are using scripts then last line will be always using to determine the exit status of a remote command executed via ssh.

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{ 10 comments… read them below or add one }

1 Jafar March 23, 2008 at 8:56 am

Suppose I put a job to run on remote server (in the background and logged. How can I check later whether the job is done or not.
Suppose if i know the Job ID ??

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2 nixCraft March 23, 2008 at 9:53 am

Use ps and jobs commands

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3 Greg Wells October 24, 2008 at 7:33 pm

You can use conditional control operators if you omit the echo $? command. The conditional operator evaluates the exit status from the echo $? command which should always be 0.

This version should work:

$ ssh root@192.168.1.16 today || echo “Command failed”

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4 vishal November 27, 2008 at 3:13 pm

I am using remsh to execute remote command.
How to obtain exit status of remotely executed command .In remote program i am using exit(number) to differinciate b/w exit status.But all time i get exit status as 0.
Even if i use abort() the exit status is 0.
SOme one help???????????/

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5 Olivier February 10, 2011 at 9:11 pm

There is an error in the article.
You have to wrap the command in quotes like this :
$ ssh user@ras.nixcraft.in ‘today ; echo $?’

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6 Leonel May 19, 2011 at 7:35 am

Additional note:
After trying this one. i found out that if ssh cannot resolve the host, the exit status is 255.

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7 Shane Holder June 21, 2013 at 8:04 pm

Um, I think the reason that

ssh root@192.168.1.16 today;echo $? || echo "Command failed"

doesn’t work is because the echo $? changes the exit status, not because of weirdness with SSH.

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8 Rahul July 23, 2013 at 12:43 pm

@Vivek / all
I want something like

ssh user@ras.nixcraft.in ” [ -e /some/path ] ”
and then $? = 0 then print file exists

“this is my first comment in your site, Jus wanna say you are doing a nice job”
-Rahul

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9 zaid Ahmed January 23, 2014 at 8:24 am

how can we pass the parameter to file which is also in command with ssh for remote execution

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10 Daniele Salvatore Albano April 17, 2014 at 12:51 pm

Just do
(ssh user@ras.nixcraft.in “command_does_not_exists” >/dev/null 2>&1) || echo “Command doesn’t exists! HOSTNAME: $(hostname)”

you can pass -i /path/to/private-key to authenticate to the remote machine using an ssh key if you don’t want to use ssh-agent or other stuff like that (useful when doing remote automations, you can use in rsync too with -e or in git using a simple wrapper)

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