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linuxsshsu

SSH remote machine and execute command

I am sshing to a remote machine and executing a command but my $PATH on the remote machine is set to the $PATH of user in the original machine and not that of sshed machine. But if I ssh to the remote machine and execute echo $PATH, it is set correctly to the logged in user in the new machine 

root@host1> ssh admin@remotemachine echo $PATH

This prints the PATH of the user, in this case root on host1 and not admin on remotemachine

root@host1> ssh admin@remotemachine 
admin@remotemachine's password: ****
echo $PATH

Above works fine

Basically it's not changing the environment to the new user on remote machine. Somehow even though i am logged in to remote machine, it preserves the environment of root from host1. If I do ls -al /, it shows the directories from the remote machine, which means i am logged in to the remote machine

Solution

  • Let's use set -x to debug what we actually run:

    $ set -x
$ ssh localhost echo $PATH
+ ssh localhost echo /usr/local/bin:/usr/bin:/bin:/usr/local/games:/usr/games
/usr/local/bin:/usr/bin:/bin:/usr/local/games:/usr/games

    The line with the + tells us that the command we actually run is:

    ssh localhost echo /usr/local/bin:/usr/bin:/bin:/usr/local/games:/usr/games

    Unsurprisingly, this is also the value we get back, regardless of what the remote PATH is.

    We can single quote the command to ensure that we send echo $PATH instead of echo /usr/local/bin:... to the server:

    $ ssh localhost 'echo $PATH'
+ ssh localhost 'echo $PATH'

    Now set -x shows that ssh is being run with the unexpanded command instead of the expanded command, and we get the remote PATH in return.