Seeing all users linux

How to check list of users in Unix

Command to check list of users in Unix

On a FreeBSD/OpenBSD/NetBSD and many other Unix-like system, just type the following cat command/more command/less command to get a list of all user accounts:
$ cat /etc/passwd
$ more /etc/passwd
$ less /etc/passwd
Sample outputs:

Understanding file format

Consider the last line:

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1. vnstat – User name
2. * – Encrypted password is stored in a in a separate file
3. 284 – UID (User id)
4. 284 – GID (Group id)
5. vnStat Network Monitor – General information about the user
6. /nonexistent – User’s home directory
7. /usr/sbin/nologin – User’s login shell

How to just display a list of user names

Use the cut command as follows:
$ cut -d: -f1 /etc/passwd
OR use awk command:
$ awk -F’:’ ‘< print $1>‘ /etc/passwd
Sample outputs:

How do I search for a given user name such as vivek

Use the grep command as follows:
$ grep ‘^userNameHere’ /etc/passwd
$ grep ‘^vivek’ /etc/passwd
Sample outputs:

How to use getent command to find out a list of users

To get entries from administrative database such as /etc/passwd use the getent command as follows:
$ getent passwd
$ getent passwd | more
$ getent passwd | grep vivek

A note about macOS Unix users

If you are using a macOS, try the following command to check list of users in Unix cli (open the Terminal app and type the following bash command):
$ dscl . list /Users
OR
$ dscacheutil -q user
The dscl is a general-purpose utility for operating on Directory Service directory nodes.

How to find which Unix users are logged in and what they are doing

How do I see available list of groups on my server?

Type any one of the following command:
$ more /etc/group
$ less /etc/group
$ grep vivek /etc/group

Display Unix account information using logins command

The logins command shows information about user and system accounts. All you have to do is type the following command:
$ logins

To get information about the password change and user account expiration times, run:
$ logins -a
Only find and display information about tom and jerry accounts:
$ logins -l userName
$ logins -l tom,jerry
Want to see Unix user accounts with no password? Pass the -p option:
$ logins -p
Finally, we can see information about each account’s home directory and shell such as csh, ksh, bash and more:
$ logins -x
$ logins -x -l vivek

Conclusion

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How to List Users on Ubuntu Linux VPS

In this article, we will show you how to list users on Ubuntu VPS. By the end of this tutorial, you’ll be able to perform some basic commands to view all registered users and groups to manage your system administration. So, without further ado, let’s get started.

Reasons to View System Users in Ubuntu

Linux is popular among tech research groups and development communities because it is suitable for team-based projects. This means that oftentimes, a Linux-based system is used by multiple users at the same time.

For that reason, managing these users and groups is a day-to-day task. System administrators can take advantage of Ubuntu’s complete features to control how users and groups interact with the system.

For instance, you can grant certain users and groups to access specific files and folders. What’s more, you can adjust configuration and administrative rights to modify your system and secure your data by preventing any harmful anonymous process.

However, before configuring those settings, it is better to learn how to list users on Ubuntu VPS or server. The reason is simple: you will need to see their permissions and activities to verify every operation on your machine.

Do note that since we will list users on Ubuntu VPS, we have to use the command line to access it. You can work with the terminal shell (Linux and macOS) or PuTTY (Windows). If you’re a Hostinger user, the login credentials are located in the hPanel’s Servers tab.

How to List Users on Ubuntu

We are going to divide this tutorial into three parts — viewing all users, viewing groups, and viewing logged in users.

Viewing All Users on Linux

Linux stores all the information about user registrations in a file called passwd, which is located at /etc/passwd.

1. To access the content of the file, open your terminal and type the following command:
2. The script will return a list that looks like this:

In the output above, each line corresponds to a user. The number of lines will depend on the number of registered users.

Each line contains seven fields that are separated by colons (:). These fields hold specific information about a particular user.

Let’s take a look at the first line:

Here are the meanings of each field, from left to right:

• root — the login name of the user.
• b — placeholder for the password (the actual password is stored in a separate file).
• 0 — User ID, which is unique for each registered user. By default, root has the User ID of 0.
• 0 — Group ID. Like User ID, it is unique for every user.
• root — Comment field. Contains a short description of the user, usually filled out with users’ full name.
• /root — Home directory. This is the main directory of the users. For users other than root, the folder will be /home/username.
• /bin/bash — User shell. Refers to the shell that users use to sign in to the system.

If you only want to view the name of the users, you can run this special command:

Viewing Groups on Linux

In Linux, you also have the option to create groups. You basically gather several users and grant them joint privileges or access. It is particularly useful if multiple teams are using the same system.

Unlike users, the group information is stored in a file named group that can be found at /etc/group.

1. To view the contents of this file, simply open up the terminal and type the following command:
2. The line above should give this output:

Notice that the group names are exactly the same as the name of our users. This is the result of user private groups (UPG), a scheme employed by Linux where each user will have their own private group.

Just like the previous one, it is possible to view the group names only:

Viewing Logged In Users

To list logged in users, simply type the following letter in your terminal:

Besides showing the active users, the command also provides some additional information like login time, remote host, and idle time. The full results will look like this:

Let’s breakdown the results of the w command:

• User ⁠— username.
• TTY ⁠— terminal name
• From ⁠— the name of the remote host.
• Login@ ⁠— login time.
• Idle ⁠— idle time.
• JCPU ⁠— the amount of time used by processes attached to the TTY.
• PCPU ⁠— the time used by the process displayed in the WHAT field.
• WHAT ⁠— the user’s current process.

Alternatively, there is another command that performs a similar function to w:

However, the results won’t be as detailed as the w command:

Conclusion

Linux is a perfect OS for team-based projects because many people can log in to the same system. Due to this nature, it is important to learn how to manage users for better system administration.

The first lesson you need to know is to list the registered users, which will be useful to verify all operations and protect your data.

In this guide, we have shown you how to list users on Ubuntu VPS using simple commands. In addition, you’ve also learned how to view all groups and monitor every logged-in user.

Good luck and be sure to check other VPS tutorials!

Domantas leads the content and SEO teams forward with fresh ideas and out of the box approaches. Armed with extensive SEO and marketing knowledge, he aims to spread the word of Hostinger to every corner of the world. During his free time, Domantas likes to hone his web development skills and travel to exotic places.

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How To View System Users in Linux on Ubuntu

Published on September 5, 2013

Introduction

A fundamental part of system administration is configuring and managing users and groups. Part of this task involves monitoring the log in capabilities of all system entities.

In this guide, we will introduce the basic ideas behind user management and authentication logging.

We will be exploring these concepts on an Ubuntu 12.04 VPS, but you can follow along on any up-to-date Linux distribution.

Part one will cover how to view system users and find out who is logged into the system.

How To View Available Users on a VPS

Every user on a Linux system, whether created as an account for a real human being or associated with a particular service or system function, is stored in a file called «/etc/passwd«.

The «/etc/passwd» file contains information about the users on the system. Each line describes a distinct user.

Have a look by entering:

Each line is broken up into fields. These fields are delimited by the colon (:) character.

The only field that we are really interested in at the moment is the first one. Each is an independent username.

We can get this list without wading through the entire «/etc/passwd» by typing:

You probably recognize «root» as the administrative user. Towards the end, you may see the user you are logged in as.

In between, you will probably see a number of other users whose usage seems at least somewhat clear. For instance, «www-data» is configured as the owner of web server processes.

This is done to separate functional privileges. That way, if an account is compromised or misused, the affect will be isolated.

How To View Available Groups on a VPS

The corresponding file for discovering system groups is «/etc/group«.

We can see the whole file by typing:

You can see that many of the group names mirror the users we discovered on our system. This is part of a configuration scheme called «user private groups«, or UPG.

User private groups create a private group for each user and set that group as the primary group. The umask is then changed from 022 to 002.

This allows for more flexibility in shared directories by setting a flag called setgid, which gives files inside the directory the same group owner as the directory itself. This configuration is useful, but outside of the scope of this article.

Once again, we can pare down the information from the «/etc/group» file by using the cut command:

The output will be a list of each group on the system, one per line.

How To Find Which Users Are Logged In

Many times, it will be more useful to find out which users are active on your system.

The «w» command is a simple way to list all of the currently logged in users, their log in time, and what the command they are currently using:

The first line contains system uptime information. The following lines describe who is logged in.

An alternative that provides similar information is «who«:

Conclusion

User authentication on Linux is a relatively flexible area of system management. There are many ways of accomplishing the same objective with very simple tools.

You should now know how to find out where your server stores its user and group information. You can also see who is logged in at any given time.

In the next part, we will discuss how to restrict access to logins.

Authentication, Part 1 — How To View System Users in Linux on Ubuntu

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3 Ways to List Users in Linux

Today different Operating Systems have the capability to use multiple users, each one with their settings and custom configurations to make things easier for administrators and operators to work in together on the same system.

Linux on the other hand is very strong on this matter as it allows multiple users to work at the same time on the system in an independent way. It can even allow a single user to open several sessions even from different locations in order to work on the system.

Here are some hints & tricks to handle users in Linux.

List all the users on Linux

Let’s say you want to create a sudo user in Linux. Probably, the very first thing to know is how to know what users are in my system. There are several ways you can obtain the list of users in Linux.

1. Show users in Linux using less /etc/passwd

This command allows sysops to list the the users that are locally stored in the system. It will give the listing in structured way as:

The structure in the above output goes as:

• User name
• Encrypted password ( x represents password is stored)
• User ID number (UID)
• User’s group ID number (GID)
• Full name
• User’s home directory
• User’s Login shell (default is bash shell)

Why so many users? Which ones are ‘real’?

The list shows a lot more users than you expected because it lists all the system users too.

Now if you want to distinguish the normal users from the system users, you can refer to the User identifier (UID) number.

Generally, a normal user has UID greater or equal to 1000. This gives you a hint that the user with UID >=1000 is a normal user and users with UID

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