Change login user in linux

How to switch between users on one terminal?

I’d like to log in as a different user without logging out of the current one (on the same terminal). How do I do that?

I asked a similar question, because I ran into issues with XDG environment variables ( $XDG_RUNTIME_DIR in particular) that were driving me nuts. -> unix.stackexchange.com/questions/354826/…

10 Answers 10

How about using the su command?

$ whoami user1 $ su - user2 Password: $ whoami user2 $ exit logout 

If you want to log in as root, there’s no need to specify username:

$ whoami user1 $ su - Password: $ whoami root $ exit logout 

Generally, you can use sudo to launch a new shell as the user you want; the -u flag lets you specify the username you want:

$ whoami user1 $ sudo -u user2 zsh $ whoami user2 

There are more circuitous ways if you don’t have sudo access, like ssh username@localhost, but sudo is probably simplest, provided that it’s installed and you have permission to use it.

I am getting this error «-su: /dev/stderr: Permission denied» after executing this command echo >>/dev/stderr on a login with su —login . , any tip? I found this btw unix.stackexchange.com/questions/38538/…

Does this allow each new user to have different, overriding values for environment variables? e.g. git config for work, open source, etc.

One finding, when I listed the env it saw that everything was in order as well as a visual inspection can go; And one thing was incorrect: XAUTHORITY=/home/user1/.Xauthority’. Not sure _why_? So X-window doesn’t work by default because the protection on ~/.Xauthority` file is: -rw——- . I made a copy and that let me run gedit as an experiment.

Generally you use sudo to launch a new shell as the user you want; the -u flag lets you specify the username you want:

[mrozekma@etudes-1 ~] % whoami mrozekma [mrozekma@etudes-1 ~] % sudo -u nobody zsh [nobody@etudes-1 ~] % whoami nobody 

There are more circuitous ways if you don’t have sudo access, like ssh username@localhost , but I think sudo is probably simplest if it’s installed and you have permission to use it

sudo -s gives you a shell like su , sudo -i simulates login like su — . Can be combined with -u $user , of course.

much more efficient. being able to «login» as a user who can’t normally login is a great asset. totally allowed me to run a database instance without messing with permissions or selinux

This command prints the current user. To change users, we will have to use this command (followed by the user’s password):

After entering the correct password, you will be logged in as the specified user (which you can check by rerunning whoami .

If you’re running Ubuntu, and if the user you want to login as doesn’t have a password set:

Enter your own password and you should be set. Of course, this requires that your user has rights to gain root privileges with sudo .

To switch the terminal session to a different user, where that user can’t exit back into the original user, use exec:

This will technically login the new user in a new term process, and close out the current one. That way when the user attempts exit or Ctrl-D, the terminal will close as though that user was the one who instantiated it, i.e., the user can’t exit back into the original user’s term. Kind of pointless, considering they can still just start a new terminal session and automatically be in the original user term login, but there it is.

EDIT: For what it’s worth, you can use linux vlock command in your ~/.bashrc to lock terminal sessions by default, requiring the password of the term session user to unlock. This would somewhat prevent the aforementioned term restart under the original user context, given the term isn’t instantiated using the non-default ~/.bashrc of the user, as configured.

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How to Change Users in Linux Command Line

Linux systems have different users and different types of users. Learn how to switch the users in Linux command line or how to change to the root user in Linux.

Linux systems have different types of users with different types or permissions as well.

Not all users can execute all commands and not all users are allowed to switch to other users neither. This all might sound confusing but, I will try to explain these so it can be easy to understand.

For the moment, here’s a quick summary of how to switch users in Linux command line.

To switch users, you need to know the password of that user. You can switch the users with this command:

To switch to root user in Ubuntu, you can use this command:

Various user types in Linux

If you list all users in Linux, you’ll see a lot of users that you didn’t know about. Who are these users? Where did they come from? I could write an entire article in regards of how users work in Linux, however, this is not the idea for this one.

Basically, there are 3 types of users in Linux:

1. System Users

These are the users that are automatically created in Linux systems to be able to run services or applications and are not intended to log in to the system (in fact you can’t log in as any of these users).

2. Regular Users

These are the (human) users who can log in to a system. Each of these users might have or not different permissions or levels in the system which is given by the groups they belong to.

3. Super Users

These are system administrators or users who can perform high-level tasks that can be considered critical or system dangerous.

Switch users in the command line

When using a Linux system you can log in with a user and then simply “switch” to another user through the same command line session. In order to do this, there is a command “su -“, which allows you to switch to become another user:

[email protected]:~$ su - janedoe Password: [email protected]:~$ 

In the above example, you need to know the password of janedoe in order to switch to that user. Which makes sense because if you are going to switch to a user, you need to know the password of that user else it will be a security risk.

Switch to root user

For security reasons, some systems have ‘root’ account blocked for direct login, either locally or remotely, so this means it will not accept someone who tries to log in using ‘root’ even with the correct password.

So, how do you perform actions as the ‘root’ user? That’s what the ‘sudo’ command allows you to.

The sudo command will basically execute anything you want in the system as if the ‘root’ was doing it. You don’t need to know the ‘root’ user’s password, in fact, probably nobody knows it or there is no password assigned to ‘root’. You only need to know your own user’s password and that user must be in the ‘sudoers’ group, which is basically the group of users which can use ‘sudo’ in the system.

Normally, it is a good practice to run the commands with sudo that needs to run with root permission like this:

But if you want to change to root user so that all the subsequent commands will be run as root, you can use:

You’ll use your own password here, not the root account’s password.

As a sudo user yourself, you can create sudo user by adding the user to sudo group.

Linux systems allow you to easily switch users or execute high-level commands with the usage of ‘su‘ and ‘sudo’ commands. And remember: with great sudo power comes great responsibility!

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How to Switch Users in Ubuntu and Other Linux Distributions [Quick Beginner Tip]

It is really simple to switch users in Ubuntu or any other Linux distribution using the terminal.

All you need to do is to know the unsername and its account password and you can switch users with su command:

You’ll be asked to enter the password of the user you want to switch to.

As you can see in the screenshot above, I changed to user prakash from user abhishek in the terminal.

There are some minor details with this method that I’ll share with you in a moment. I’ll also share the graphical way of switching users in Linux if you are using desktop Linux.

If you want to switch to the root user in Ubuntu, you can use the following command:
sudo su
You’ll have to enter your own user password here.

Change user in Linux command line

Let’s see things a bit in detail. To switch users, you need to first know the exact username because tab competition doesn’t work here. You can list all the users in Linux command line by viewing the content of the /etc/passwd file.

You’ll also need to know the password of the user account you want to switch to. This is for security reason, of course.

If you are the admin user or have sudo access, you can change account password with passwd command.

You’ll notice that some people use a — between su and the username. There is a specific reason for that.

When you use -, -l or –login option, you start the shell as a login shell. This means that it will initialize the environment variables like PATH and changes to the home directory of the changed user. It will be as if you logged into the terminal as the second user.

Note: though — is more popular, it is advised to use –login option.

Change users in Linux graphically (for desktop Linux)

If you are using desktop Linux, the above method may not be sufficient for you. Why? Because you switch the user in the terminal only. It is confined to the terminal. Nothing is changed outside the terminal.

If you want to switch users so that you can log in as another user and use all the system (browser, applications etc) graphically, you’ll have to log out and then log back in.

Now the screenshots may look different but the steps remain the same. Here’s how to switch users in Ubuntu Linux.

Go to the top right corner and click the Power Off/Log out option to open the dropdown and you can choose either of Switch User or Log Out.

• Switch User: You get to keep your session active (applications keep on running) for current user. Good for temporarily switching users as you won’t lose your work.
• Log out: Current session ends (all applications are closed). Good when you want to switch to the other user for a long time.

You can choose whichever option is more suited for your need.

Now, you’ll be at the login screen with all the available users for your system. Choose the user account of your choice.

Clearly, you need to know the password of the user account you want to use.

That’s it. I hope you find this quick beginner tip helpful in changing users in Ubuntu and other Linux distributions. Questions and suggestions are always welcome.

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