Login as another user in linux

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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Login as non-root user in terminal

This is a question that I would expect to quickly get an answer from google. However somehow google is failing me. Let’s assume I’m logged in to a terminal session and I would like temporarily work as another non-root user whose password I know without leaving my session. When logged as this user I want the home directory, etc, for this user set up correctly until I log out. How do I do that? I tried

and then keying in the password, it did not produce any error but I saw no visible changes of the command prompt it would still say myname@myhost. The home directory also was that of myname and not the new login I tried to login as. I’m — as it’s apparent now — quite inexperienced in linux/Ubuntu, so any info is welcome.

2 Answers 2

To which user you want to change to?

The problem is that you are trying to «su» into a user that does not have a shell assigned to it. Most of the users such as mysql, pulse, etc, created by the system or by some packages when you install software does not have a shell assigned.

You can check if a user has a shell assigned by looking into the /etc/passwd file, just look at the end of the line of each user, if it says /bin/false it means that it does not have a shell assigned, if it has something like /bin/bash or any other shell, then you should be able to «su» into that user.

When i say «shell assigned» it basically means that it has «shell access»

still if the user does not have shell access, you can always execute commands as that user with

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How to Switch Users in Ubuntu 22.04

Linux operating system allows multiple users to perform tasks on a system without affecting the other users. Every user has a separate home directory and login name, which is not accessible to other users. The administrator can manage and create multiple users to grant them specific privileges. Somehow, the administrator may have to switch between numerous users to have some specific privileges. So, it’s an essential administrative task to switch users in Ubuntu 22.04.

This post will demonstrate multiple ways to switch users in Ubuntu 22.04. The post’s content is as follows:

Method 1: Switch User Using CLI

In this section, we will switch the user via the terminal. The “su” command is used to switch users in Ubuntu, To switch users in Ubuntu, the “su” command is used. The general syntax of the “su” command is as follows:

Example: Switch a User

There can be multiple users in a system; we can switch the user within the system with the “su”command. To change the current user to a user named “Peter”, run the below-mentioned command:

The output shows that the user is immediately switched to the new user after executing the command.

To verify whether the user is switched or not, the “whoami” command may be used:

Example: Switch to a Different User as Login User

If you want to start a shell as a login shell, that means you will log in as another user but uses the rights (sudo, etc..…) of the login user. It will change the Home directory of the new user and also initializes the environment variables. The command provided below will switch the user to “peter”:

The above screenshot shows the switching has been successfully performed.

Method 2: Switch User Using GUI

To switch the user using the GUI approach, we need to log out from the current session and log in with a different user. To do so, the process is described below:

Click on the “Power” icon at the top left (Adjacent to the Volume icon). It will show a list of options; now click on the “Power Off/Log Out” button, which will open a dropdown list. Choose the “Switch User” option to sign out:

It will log you out of the current session and redirect you to the “Start” window of Ubuntu 22.04 where you can find all the users in the system. Click on the desired one and then :

Now, you can switch the user and log in again.

That’s all from this guide!

Conclusion

The GUI and CLI methods are used to switch users in Ubuntu 22.04. In the command line method, use the “su ” command to switch users. Moreover, to switch users as login users, you may use the “su -l ” command. Apart from that, the GUI method is also demonstrated to switch users in Ubuntu 22.04. This post has demonstrated a list of methods to switch users in Ubuntu 22.04.

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

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

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

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