I would like run remote ssh commands and have them always load server-side startup files by default. I am looking for a solution that does not require:

• configuration by root


• adding extra boiler plate to the command each time


• duplicating environment variables across multiple files

I am not looking to transport local environment variables to the remote shell. I want to run a remote command using the vanilla ssh <host> <command> syntax and have it run using the same environment a remote login session would get.

Background

The below assumes bash is being used for simplicity

By default, remote ssh commands start a non-interactive, non-login shell. Quoting the man page:

If command is specified, it is executed on the remote host instead of a login shell.

You can see this more explicitly on the shell by running:

# the lack of 'i' indicates non-interactive
$ ssh localhost 'echo $-'
hBc 

$ ssh localhost 'shopt login_shell'
login_shell     off

But what if your remote command needs certain environment variables set? Being a non-interactive, non-login shell means neither .bash_profile or .bashrc will be sourced.

This is problematic, for example, if you're using tools like perlbrew or virtualenv and want to use your custom interpreter in the remote command:

$ which perl
/home/calid/perl5/perlbrew/perls/perl-5.20.1/bin/perl

$ ssh localhost 'which perl'
/usr/bin/perl

Solutions that do not satisfy the requirements above

Explicitly invoke a login shell in the remote command

$ ssh localhost 'bash --login -c "which perl"'

Requires extra boiler plate each time

Explicitly source your profile before the command

$ ssh localhost 'source ~/.bash_profile && which perl'

Requires extra boiler plate each time

Set environment variables in ~/.ssh/environment

Requires root to enable this functionality on the server

Duplicates environment variables already set in server startup files

Set ENV and BASH_ENV

Does not work: .bash_profile and .bashrc aren't sourced

Setting in ~/.ssh/environment works, but requires root access to enable

Preface the command with the environment variables you need

Requires extra boiler plate each time (potentially a lot)

Duplicates environment variables already set in server startup files

Related posts

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dot file not sourced when running a command via ssh