List All The Groups In Linux

This is going to be a simple enough article where we list all the groups in Linux – specifically your Linux. (Your list of groups may not be the same as my list of groups, of course.) This isn’t complicated but might be important to some of you, so we might as well write about it.

I’ve often mentioned that Linux is a true multi-user operating system. That is, you have many users, each with assigned tasks and permissions. You have users for everything from root to printing.

Well, along those same lines, Linux also uses groups. You can not only set permissions on a per-user basis, you can set permissions on a per-group basis. Any member belonging to that group will have the same permissions as that group.

A good example is ‘sudo‘. That’s a group you likely belong to. Because you belong to the sudo group you have access to the sudo command. This lets you have elevated permissions to perform various operations on your system. Make sense?

We’ll be using a new tool for this…

getent:

The getent command is used to read various databases. This is fine because ‘groups’ is one of the databases that getent can read. You won’t need to install anything to run this command.

You can check the man page with this command:

From there, you’ll see that getent is described like so:

getent – get entries from Name Service Switch libraries

So, it’s a database reading tool more than anything else.

If you’d like an easier way, we’ll do the same with the cat command.

cat:

I really shouldn’t have to describe the cat command. We’ve used it plenty of times. It takes the contents of a file and spits them out to your terminal (standard output). It’s an oft-used tool in the Linux world. Once again, you won’t have to install anything.

You can check the man page with this command:

At that point, you’ll see that the cat command is described like this:

cat – concatenate files and print on the standard output

See? It’s the correct tool for the job. We want to take the contents of a file and read it in the terminal. The cat command is perfect for that.

I’ll show you how to list all the groups in Linux with both commands. You can pick your favorite and just use that command. Either command will work just fine for this job.

List All The Groups In Linux:

If it wasn’t obvious from the above, this is yet another task for the terminal. If you don’t have an open terminal, you can probably open one by pressing CTRL + ALT + T. If that doesn’t work, find the terminal in your application menu and click it.

With your terminal open, run the following command:

While not of much use, here’s an example output:

You can get the same output with the cat command. That might be easier to remember for newer users. After all, you should be familiar with the cat command. That command is simple enough.

That will give you the same results as the ‘getent’ command above. Obviously, the group name is the first column.

I’m not sure where I learned this, but you can just list the first field and get a list of groups without any additional information. Just use this command:

That’s not nearly as useful as it could be, but I figured I’d share.

Closure:

Well, if you wanted to list all the groups in Linux, you now know how to do so. If you didn’t know about groups, you now know that you have groups and how to list them. So, you might as well add that to your notes and keep it in mind. (The groups subject may appear in a future article!)

Thanks for reading! If you want to help, or if the site has helped you, you can donate, register to help, write an article, or buy inexpensive hosting to start your site. If you scroll down, you can sign up for the newsletter, vote for the article, and comment.

Create A New User

Today’s article is going to be quick and easy as we simply discuss how you create a new user. This is a fairly basic task and shouldn’t take too long to cover. If you want to create a new user, read on!

If it’s not obvious,  you have a user account. You use this information even if you don’t realize it. Indeed, you use this information when you log into your computer to begin with. When you log in, you’re logging into your user account.

There are other users. You may have a root account or an account for MySQL. If you want to know how many different users are on your system, you can follow along with the following article:

How To: List All Users In Linux

One of the things that helps keep Linux secure is that it’s a true multi-user environment. You can only perform operations on the files you have access to. This is why you use sudo or root.

Managing users is a fundamental task in Linux. This article is going to cover how to create a new user and we’ll be doing so in the terminal. This should be fairly universal and you won’t need to install anything as user management tools will be included by default.

We will use a couple of tools, however. The first among them is:

useradd:

The useradd command is basic and, as the name implies, is used to add new users. There’s nothing complicated about it in today’s article and you can be certain that this is already a tool available to you.

If you’re curious about the command, check the man page:

If you do so, you’ll see that it’s described as this:

useradd – create a new user or update default new user information

So, that’s the correct tool for this job.

passwd:

The other tool we’ll be using is the passwd command. You can again tell by the name what the tool is going to do. Simply, it’s used as a password management tool. This too isn’t all that complicated and you can check the man page with this command:

If you do so, you’ll see that I wasn’t kidding and that this tool does what you think it does. It’s described like so:

passwd – change user password

This is the correct tool for the job. After we create a new user, we’ll assign them a password. If the user wishes, they can change that password on their own.

Create A New User:

As mentioned above, we’ll create a new user with terminal-based tools. This is a nice and universal way to do things. Sure, there are GUI tools out there but this is going to work on any Linux system you’re likely to engage with. You can crack open your favorite terminal, often by just pressing CTRL + ALT + T on your keyboard.

First, we’ll create a new user with the useradd command. The syntax is very simple:

For example:

Now, we’ll add a password. This is also a simple command:

For example:

You’ll be asked to enter the password a couple of times. This is to help ensure that you’ve not made any typographical errors while entering the password. It’s all basic stuff.

Next, you can verify that the new user account has been created. For this next step, we’ll simply use cat and grep.

Again, here’s an example:

The output should look a little something like this:

If you find your user, you’ve done this properly and you’ve learned how to create a new user. I told you that it wouldn’t be too complicated!

Closure:

So… This is an article about how to create a new user. It’s a pretty basic task but one you might just want to know about. You never know when you’ll need to create a new user but now you know where to look if you do need to. User management can be a pretty important task, especially for a server admin.

Thanks for reading! If you want to help, or if the site has helped you, you can donate, register to help, write an article, or buy inexpensive hosting to start your site. If you scroll down, you can sign up for the newsletter, vote for the article, and comment.

Create A New User In Linux

If you’re familiar with Linux, you’ll already know that Linux is a multiuser system and today we’ll learn how to create a new user in Linux. This shouldn’t be a very complicated article. In some more advanced operations, you may be required to create a new user. This article will be about that.

If you aren’t already aware, you have a whole lot of users on your Linux system. You have more users than just your user account and certain things can be done by certain users. You can generally use an elevated account (or sudo) to overcome those user restrictions.

There may come a time when you want to share your device with another person. So, there’s another reason to create an additional user. If you’re managing a server with multiple users, there’s another reason to create a new user in Linux. There are any number of reasons why you’d like to create a new user and we’ll go over that process today.

We’ll just be using a couple of tools today. It’s not complicated.

useradd:

The main tool we’ll be using is the useradd command. This is a tool that’s certainly installed by default on any major distro. It’s a part of the basic building blocks we use to manage Linux, so this doesn’t require any installation. You can verify that you have useradd available with the following command:

The output should be:

If you check the man page, you’ll see this:

useradd – create a new user or update default new user information

So, as our goal is to create a new user, you can see that this is the correct tool for the job. I can’t think of a better tool for the job, as it should do everything behind the scenes as well.

passwd:

We’ll also be using the passwd command. This isn’t strictly necessary, but it’s in your best interest to set a user’s password. Once again, you won’t need to install anything and the following command will confirm that:

The output should match this output:

The text alone should let you know that this is a tool for setting passwords, but you can always refer to the man page to learn more. This is how passwd is described:

passwd – change user password

As I said, you don’t have to undergo this step but it’s in your best interests, from a security standpoint, to assign passwords to users who have any access to your system. And, as you can see, this is the right tool for the job of setting a user’s password.

Create A New User In Linux:

Of course, this is done in the terminal. As a general rule, you can press CTRL + ALT + T and your default terminal should open. That’s a fairly common shortcut that I mention often. You can also find a terminal in your application menu, pretty much regardless of which desktop environment you’re using and whichever Linux you’re using.

Creating The New User:

With your terminal now open, you’ll need to use elevated privileges, and the syntax is quite simple. To create a new user in Linux, the syntax follows:

This should be lowercase as Linux doesn’t like capital letters in usernames. So, for my username, the command would look like this:

You can confirm that you’ve added the user with the following command:

For example:

With your user firmly in place, you should set a password. Let’s do that next.

Set A Password For Your New User:

You’re almost always going to want a password for your new user. That’s easily done and also requires elevated permissions. You’ll need to continue using the terminal when you want to set a new password for the user.

The syntax for setting a password for your new user is as follows:

After you authenticate, the system will have you type in the password twice. It does this to ensure you’ve not made a mistake while typing, though it could be that you’ve made the same mistake twice.

So, be careful with this step. Otherwise, you have to find some way to reset the new user and the quickest way to do that would be to delete the user and start again.

Closure:

Yeah, I guess this counts as a short article. My most recent articles have been longer than this one. This one is about the length of my earliest articles, maybe slightly longer. The site has evolved!

Anyhow, you’ve learned how to create a new user in Linux. It shouldn’t matter which distro you’re using. The kernel you’re using shouldn’t impact this at all. It shouldn’t even matter what shell you’re using, this should simply work. If you want to create a new user, this is how you do it.

Thanks for reading! If you want to help, or if the site has helped you, you can donate, register to help, write an article, or buy inexpensive hosting to start your site. If you scroll down, you can sign up for the newsletter, vote for the article, and comment.

How To: Show User Information In The Linux Terminal

There comes a time in many Linux journeys when you want to know how to show user information in the Linux terminal. Well, if you’ve been waiting for such an article, this article is for you. After all, knowing about the various users might be important information for you.

You may not realize this, but your Linux system has all sorts of users. They belong to varied groups, sometimes more than one group at a time. Unless you’re already familiar with this subject, you probably have more users than you realize. 

That’s perfectly okay. It’s entirely normal to have different users. Linux is a user-oriented operating system. Users have varied permissions and can perform different tasks based on those permissions. 

This actually shouldn’t be a complicated article. It’s just a couple of commands, though the command may not be well-known among the newer Linux users. New users should familiarize themselves with the concepts of a multi-user system and with groups.

Anyhow, you shouldn’t need to install anything. The tools we’ll be using should be installed by default. You will need an open terminal. So, you have been warned. After all, it was right there in the title!

lslogins:

The tool we’ll expose you to today is ‘lslogins‘, which should be installed by default. You can verify that lslogins is installed with this command:

And, if you check the man page (with man lslogins) you’ll see this:

lslogins – display information about known users in the system

So, sure enough, that looks like it’s the correct tool for the job. Our goal is to show user information in the Linux terminal. This looks like a good way to go about it.

Show User Information In The Linux Terminal:

Yes, we’re doing this in the terminal. You can frequently open your terminal by pressing CTRL + ALT + T. Otherwise, you’ll find a terminal emulator somewhere within your application menu. It’s likely to be in the admin section of said menu.

With your terminal open, you can start with the basics. That is, we’re going to show all the known users with the lslogins command. That syntax is so simple.

You’ve got a lot of users. You may not know it yet, but you do. Here’s an example output from my system:

Now, that’s all well and good.

But…

Let’s say you only want to show user information about one single user. That’s fine and you can do that in a variety of ways. You can also do it just as easily with the lslogins command, simply by using the -u flag. 

The syntax is as follows:

An example output might look like this:

And there’s the information about the root user. You can try with your username and get information about things like the groups you belong to and more. Go ahead and give it a shot, you won’t break anything. I promise you won’t break anything with this command!

Closure:

You never know when you’re going to want to show user information in the terminal. It is useful information, especially when debugging things like permission errors. You may find you need to add yourself to a group or things like that. So, store this command away in your mental bank and save it for when you need this information.

Thanks for reading! If you want to help, or if the site has helped you, you can donate, register to help, write an article, or buy inexpensive hosting to start your site. If you scroll down, you can sign up for the newsletter, vote for the article, and comment.

How To: Kill A User Session

Today’s article won’t be useful for many of my regular readers because it’s about how to kill a user session. This is a skill worth learning, but really only applies to computers that have multiple people logged in at one time. If that’s describing you and your needs, this may be an article worth reading.

Of course, if that’s not something you do, you can still learn from this. It’s not all that complicated and is easy enough to follow. So, feel free to learn something – even if it isn’t something you’re likely to ever need.

There are times when you may have someone logged in and you want to log them out. For example, let’s say you’re getting ready to fire someone. You’re going to want to delete their account, make sure they’re logged out of their account, and then take them to HR where you can file paperwork and escort them (and their property) off the site.

You might also want to do stuff like log people out so that you can perform updates on the server. There are all sorts of reasons why you might want to kill a user session. Your reasons are your own. I’ll simply be showing you the tools.

Kill A User Session:

You’ll need an open terminal and to be connected to the computer you want to control. If you’re doing this, I’ll assume you’re aware of how to do those things. If you’re doing this on your own computer, you can usually press CTRL + ALT + T and your default terminal should open.

Once you’re connected (or have your own terminal) you can find the logged-in users with the following command:

Actually, you can just use this command:

The results are the same. So, either works.

You can now see the output which will show you every logged-in user on that device. Next, you’ll kill a user session with the following command:

If you wanted to use the kill command, you could find the associated processes (the PID) but there’s no reason to do so when you can just kill a user session with the username.

Closure:

There you go. I figured I’d do a nice, short, and easy article. It’s not very complicated and it’s not something many of you will need. However, if you’re managing a system with multiple people logged in, this is a very useful tool to have. You never know when someone’s going to come into your office and ask you to kill a user session. Well, now you know how…

Thanks for reading! If you want to help, or if the site has helped you, you can donate, register to help, write an article, or buy inexpensive hosting to start your site. If you scroll down, you can sign up for the newsletter, vote for the article, and comment.

Subscribe To Our Newsletter
Get notified when new articles are published! It's free and I won't send you any spam.
Linux Tips
Creative Commons License
This work is licensed under a Creative Commons Attribution 4.0 International License.