Passing Environment Variables to Sudo Command
By Pete Freitag

Suppose you have a bash script that sets an environment variable, and then invokes something with sudo:
#!/bin/bash export MY_VAR=test sudo /do/something
You will find that the environment variable you set using export
is not available to the /do/something
command.
When you run sudo, you are actually starting a new environment as the root user (or whatever user you have instructed sudo to run as), so any environment variables that exist in your current shell will not be passed. There are two ways to get around this.
Tell sudo to preserve environment
The sudo
has a handy argument -E
or --preserve-env
which will pass all your environment variables into the sudo environment.
Passing only the variables you need
A better approach is to just pass the environment variables you want to preserve, instead of passing everything. There are two ways to accomplish this, first you can supply a list of environment variable names to the --preserve-env
argument. For example:
sudo --preserve-env=HOME /usr/bin/env
Finally you can also set environment variables directly in the sudo
command, like this:
sudo ZEBRA=true /usr/bin/env
Note, we are using the /usr/bin/env
command above, which simply echo's all the environment variables. That is just a handy way to test which variables are in the current environment.
Passing Environment Variables to Sudo Command was first published on September 23, 2019.
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Comments
--preserve-env=list
Indicates to the security policy that the user wishes to add the comma-separated list of environment variables to those preserved from the user's environment.