Environment-Variables – How to Permanently Set Environmental Variables

environment-variables

My variables are

LD_LIBRARY_PATH=/usr/lib/oracle/11.2/client64/lib
ORACLE_HOME=/usr/lib/oracle/11.2/client64

How to save these variables permanently ?

Best Answer

You can add it to the file .profile or your login shell profile file (located in your home directory).

To change the environmental variable "permanently" you'll need to consider at least these situations:

Login/Non-login shell
Interactive/Non-interactive shell

bash

Bash as login shell will load /etc/profile, ~/.bash_profile, ~/.bash_login, ~/.profile in the order
Bash as non-login interactive shell will load ~/.bashrc
Bash as non-login non-interactive shell will load the configuration specified in environment variable $BASH_ENV

$EDITOR ~/.profile
#add lines at the bottom of the file:  
     export LD_LIBRARY_PATH=/usr/lib/oracle/11.2/client64/lib
     export ORACLE_HOME=/usr/lib/oracle/11.2/client64

zsh

$EDITOR ~/.zprofile
#add lines at the bottom of the file:  
     export LD_LIBRARY_PATH=/usr/lib/oracle/11.2/client64/lib
     export ORACLE_HOME=/usr/lib/oracle/11.2/client64

ksh

$EDITOR ~/.profile
#add lines at the bottom of the file:  
     export LD_LIBRARY_PATH=/usr/lib/oracle/11.2/client64/lib
     export ORACLE_HOME=/usr/lib/oracle/11.2/client64

bourne

$EDITOR ~/.profile
#add lines at the bottom of the file:  
     LD_LIBRARY_PATH=/usr/lib/oracle/11.2/client64/lib     
     ORACLE_HOME=/usr/lib/oracle/11.2/client64
     export LD_LIBRARY_PATH ORACLE_HOME

csh or tcsh

$EDITOR ~/.login
#add lines at the bottom of the file:  
     setenv LD_LIBRARY_PATH /usr/lib/oracle/11.2/client64/lib
     setenv ORACLE_HOME /usr/lib/oracle/11.2/client64

If you want to make it permanent for all users, you can edit the corresponding files under /etc/, i.e. /etc/profile for Bourne-like shells, /etc/csh.login for (t)csh, and /etc/zsh/zprofile and /etc/zsh/zshrc for zsh.

Another option is to use /etc/environment, which on Linux systems is read by the PAM module pam_env and supports only simple assignments, not shell-style expansions. (See Debian's guide on this.)

These files are likely to already contain some assignments, so follow the syntax you see already present in your file.

Make sure to restart the shell and relogin the user, to apply the changes.

If you need to add system wide environment variable, there's now /etc/profile.d folder that contains sh script to initialize variable.
You could place your sh script with all you exported variables here.
Be carefull though this should not be use as a standard way of adding variable to env on Debian.

Related Solutions

Set global environment variables at boot in Solaris 11

If these variables need to be set for every account, the simpler would be to add the export statements to /etc/profile. This file is not root's profile but a file sourced for every account using an interactive Bourne shell family shell (sh, ksh, bash, ...)

You can then just add at the end of this file.

export ORACLE_HOME=/oracle/product/11.1.0/db_1/
export ORACLE_SID=orcl
export TESTFOLDER_DIR=/test/testfolder/bin/

Otherwise, just add these three lines in your shell startup file (likely one of $HOME/.profile or $HOME/.bash_profile).

If you are logging in as root (which is not a good practice), that would be /.profile or /root/.profile

Finally, should you want to unconditionally set these variables whatever the shell is used and even for non interactive login stuff, like services, you can use the /etc/default/init file. Note that the export builtin is not required in this file as it is not a real shell script but really a configuration file, eg:

ORACLE_HOME=/oracle/product/11.1.0/db_1/
ORACLE_SID=orcl
TESTFOLDER_DIR=/test/testfolder/bin/

systemd – How to Set Environmental Variable in Systemd Service

Normally systemd services have only a limited set of environment variables, and things in /etc/profile, /etc/profile.d and bashrc-related files are not set.

To add environment variables for a systemd service you have different possibilities.

The examples as follows assume that roscore is at /opt/ros/kinetic/bin/roscore, since systemd services must have the binary or script configured with a full path.

One possibility is to use the Environment option in your systemd service and a simple systemd service would be as follows.

[root@localhost ~]# cat /etc/systemd/system/ros.service
[Unit]
Description=ROS Kinetic
After=sshd.service

[Service]
Type=simple
Environment="One=1" "Three=3"
Environment="Two=2"
Environment="Four=4"
ExecStart=/opt/ros/kinetic/bin/roscore

[Install]
WantedBy=multi-user.target

You also can put all the environment variables into a file that can be read with the EnvironmentFile option in the systemd service.

[root@localhost ~]# cat /etc/systemd/system/ros.env
One=1
Three=3
Two=2
Four=4


[root@localhost ~]# cat /etc/systemd/system/ros.service
[Unit]
Description=ROS Kinetic
After=sshd.service

[Service]
Type=simple
EnvironmentFile=/etc/systemd/systemd/ros.env
ExecStart=/opt/ros/kinetic/bin/roscore

[Install]
WantedBy=multi-user.target

Another option would be to make a wrapper script for your ros binary and call that wrapper script from the systemd service. The script needs to be executable. To ensure that, run

chmod 755 /opt/ros/kinetic/bin/roscore.startup

after creating that file.

[root@localhost ~]# cat /opt/ros/kinetic/bin/roscore.startup
#!/bin/bash

source /opt/ros/kinetic/setup.bash
roscore


[root@localhost ~]# cat /etc/systemd/system/ros.service
[Unit]
Description=ROS Kinetic
After=sshd.service

[Service]
Type=simple
ExecStart=/opt/ros/kinetic/bin/roscore.startup

[Install]
WantedBy=multi-user.target

Note that you need to run systemctl daemon-reload after you have edited the service file to make the changes active. To enable the service on systemboot, you have to enter systemctl enable ros.

I am not familiar with the roscore binary and it might be necessary to change Type= from simple (which is the default and normally not needed) to forking in the first two examples.

For normal logins, you could copy or symlink /opt/ros/kinetic/setup.bash to /etc/profile.d/ros.sh, which should be sourced on normal logins.