See all users and groups in linux

Show all users and their groups/vice versa

I know I have existing groups and users but I’m not sure about their association. Is there an shell command I can use to list all users or all groups and a command to list all groups/users for a specified user/group? So something like showusers would list all users, and showgroups -u thisuser would show all the groups that have thisuser in it.

8 Answers 8

All groups with a specific user:

$ getent group | grep username 

I found that there is a user named speech-dispatcher that belongs to group audio (based on groups speech-dispatcher ). But it is not listed under getent group command! What is the problem?

+1 since this will also list users/groups not found in the conventional /etc/passwd & /etc/group files i.e. when a system is configured to use central directories such NIS and LDAP, or any other alternative user/group database, as long as that supports user/group enumeration.

List users and their groups:

for user in $(awk -F: '' /etc/passwd); do groups $user; done 

List groups and their users:

cat /etc/group | awk -F: '' | while read group gid members; do members=$members,$(awk -F: "\$4 == $gid " /etc/passwd); echo "$group: $members" | sed 's/,,*/ /g'; done 

While that would probably work, it seems a bit overly complicated, doesn’t it, when there are perfectly good simple one-shot commands to do this?

It certainly wouldn’t get anything that lives in a centralized repository. And that’s definitely information that you’d want to see.

If you dont care about remote users such as LDAP or NIS, to list users and their associated groups in a simple way:

cut -d: -f1 /etc/passwd | xargs groups 

root : root myuser : root www-data fuse anotheruser : anotheruser cdrom floppy audio dip video plugdev scanner bluetooth netdev 

This has the same problem as Chang’s answer in that it ignores users/groups originating in databases such as LDAP, NIS, etc.

This very neatly outputs the information in an incredibly clear format though, so can still be a useful first step. It helped jog my memory regarding the syntax of /etc/group and /etc/passwd!

List all users

While cat /etc/passwd shows all users (and a bunch of other stuff), cut -d ‘:’ -f 1 is a simple way to split each line with ‘:’ as a delimiter and extract just the first field (users). Pretty much the same as awk version.

List all groups

Guess what, very simmilar to listing users. Just parse /etc/group instead.

Another interesting way, maybe closer to what OP wanted, is compgen. Not sure about compatibility issues though.

Hi Elliot Baily, welcome to Server Fault! Please note that this question is over 5 years old, and already has a correct and accepted answer. Also note that your solution only works if users are stored in /etc/passwd; the accepted answer also works for other user databases (such as NIS or LDAP). If you want to answer old questions (which is perfectly fine!) you might want to have a look at the list of unanswered questions — plenty of questions looking for some love!

for user in $(getent passwd |awk -F: ''); do groups $user; done 

cat /etc/passwd # show all users cat /etc/group # show all groups cat /etc/passwd | grep group # show all users with specified group 

In contrast with the already accepted this does not list users/groups that originate from a remote user database such as LDAP, NIS etc.

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How can I display all users and groups with a command?

users and groups commands display users currently logged in, and groups a user belongs to respectively.

How to display a list of all users and all groups by command-line?

2 Answers 2

You can display with the help of compgen builtin command as follows:

To display all users run following command:

However you can also display all users by cut -d «:» -f 1 /etc/passwd .

Nice! it might be preferable to use getent passwd / getent group instead of cat’ing the local files ( getent should work for non-local accounts as well)

Well, on my ubuntu, I have some files created by docker mount with 999:999 as user:group , but unfortunately none of the above commands prints them.

Here we are going to use getent for the detailed the info

We can list the user with the following command:

We can list the group as follows:

To fetch detail a specific user

Replace the lalit with your user name. Lalit will not be in every system 🙂

You can read the more into about getent here

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How To List All Users and Groups in Linux

Users and group files are important for Linux. Normal users will interact with Linux systems by using credentials provided in the user ad group file.

Print User File Named passwd

We can get content of the user file like below. This file provides usernames home directories and shell information.

As we can see each line of the output provides the user name, user id, user group, user shell, user home path etc.

Print Only Usernames

We can print only usernames by filtering other columns like below.

$cat /etc/passwd | cut -d : -f 1

Print Users Who Have Login

By default normal users will login to the Linux box. But in some cases service users do not need to login Linux system. This is also a security measure. We can list users who do not have login right with the following command. This login information is stored in the /etc/passwd file.

$ cat /etc/passwd | grep -v nologin

Print Users Who Have Home Directories

We can print only users who have home directories in /home. This command will first look in to the passwd to list users how have /home and then print only user names from result.

$ cat /etc/passwd | grep "/home/" | awk -F':' '< print $1>'

Print Group File

Linux users have primary and secondary groups. These group names are stored in the /etc/group file. We can print this group information and assigned user with cat command. For more details read following tutorial.

Print Only Group Names

We can print only group names by cutting other column like below.

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How to List Users in Linux

User management is a critical Linux system administration task. In large organizations, having insight into who has access to the system is crucial to correctly add users, remove users, and assign new user privileges.

This tutorial will show you how to list users on a Linux-based system. The guide provides four listing methods and explains essential concepts related to user administration.

Listing Users in Linux

Linux stores information about local users in the /etc/passwd file. Each line in the file contains information about a single user, including their username, user ID number (UID), home directory, and the login shell.

The following sections present multiple ways to access the data in /etc/passwd and list users on Linux distributions.

The commands used in the tutorial are:

Note: To display a list of the logged-on users and the information such as boot time, processes, hostnames, and more, use the who command.

List Users with cat Command

The cat command provides a straightforward way to list the contents of the /etc/passwd file.

The system outputs the entire file with all the users on the system.

To view the number of users only, pipe the output of the previous command to the wc command and make it count the number of lines:

The number of lines in /etc/passwd corresponds to the total number of users.

List Users with Terminal Pagers less and more

On systems with many users, it is useful to limit the /etc/passwd file output displayed at once. Use a terminal pager command, such as less or more , to browse through the file content line by line or page by page.

To open /etc/passwd using less , enter:

The first page of the file appears in the output. The list stops when it reaches the end of the terminal screen. Use the keyboard to navigate through the file.

Use more to get a similar result. This command is older and has a more limited set of functionalities:

List Users with awk Command

Use the awk command to list the usernames only, without additional information about each user. Since the data fields in /etc/passwd are separated by a colon symbol, the following syntax tells awk to output only the first field in each line:

Combine awk and less for a page-by-page view of the results.

List Users with getent Command

The getent command searches and displays system database entries. The searchable databases are listed in the /etc/nsswitch.conf file. By default, the file includes the passwd database.

List the entire contents of the passwd database by typing:

The output is the same as the output of the cat command.

However, you can use getent to look up specific users. To do so, use the following syntax:

If the user exists on the system, the command shows the related passwd entry line.

Listing Normal and System users in Linux

Linux-based systems have two types of users — system and normal users.

• System users are entities created by the system to run non-interactive processes, i.e., the processes that run in the background and do not require human interaction. The most important system user is root, which possesses administrative privileges.

• Normal users are human users created by root or another user with root privileges. Each normal user has a login shell and a home directory to store their files.

Both system and normal users in Linux have a unique user ID (UID) to identify them. System users have UIDs in the range from 0 (root user) to 999. Normal users typically receive UIDs from 1000 onwards, with each newly created user receiving the next smallest unused UID.

To check the UID range for normal users, use the grep command to search for the information stored in /etc/login.defs :

grep -E '^UID_MIN|^UID_MAX' /etc/login.defs

The output in this example shows that the smallest UID a normal user can receive is 1000, and the largest is 60000.

Use getent to search the passwd database by UID:

The output shows the user entry related to the UID.

Use UIDs in combination with getent to search for users in a range:

The command now lists all the users within the specified UID range.

This guide showed you how to list all Linux users, search for users, and find the number of Linux users in any Linux distribution.

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