how to create a user without useradd command in linux?

Follow these steps to create a user without using useradd command in Red Hat Linux.

Step 1

Add an entry of user details in /etc/passwd

The field details are as shown below

username:password:UID:GID:Comments:Home_Directory:Login Shell

# vi /etc/passwd

user:x:501:501:test user:/home/user:/bin/bash

Step 2

You will have to create a group with same name. So add a new entry in /etc/group

# vi /etc/group

user:x:501:

Step 3

Assign a password to the user

# passwd user

Changing password for user user.

New password:

Retype new password:

passwd: all authentication tokens updated successfully.

mkdir /home/user

chown user:user /home/user

Now let us try to login with our newly created user

# su - user

-bash-4.1$

You should see [user@linuxforfreshers.com]$ instead of -bash-4.1$ prompt. So why does this happens?

Let us check the contents of its home directory

-bash-4.1$ ls -al

drwxr-xr-x 2 root root 4096 Jan 16 14:27 .

drwxr-xr-x. 3 root root 4096 Jan 16 14:27 ..

So, as you see none of the default contents of a normal user home directory is present like .bashrc, .bash_profile etc.

Final Step 4

NOTE: /etc/skel directory contains all the defaults files which are present inside the home folder of any user

So, copy the contents from /etc/skel inside /home/user using the below command

[root@linuxforfreshers.com ~]# cp -v /etc/skel/.* /home/user/

cp: omitting directory `/etc/skel/.'

cp: omitting directory `/etc/skel/..'

`/etc/skel/.bash_logout' -> `/home/user/.bash_logout'

`/etc/skel/.bash_profile' -> `/home/user/.bash_profile'

`/etc/skel/.bashrc' -> `/home/user/.bashrc'

`/etc/skel/.emacs' -> `/home/user/.emacs'

cp: omitting directory `/etc/skel/.gnome2'

cp: omitting directory `/etc/skel/.mozilla'

Now re login to the user

[root@linuxforfreshers.com ]# su - user

[user@linuxforfreshers.com]$

And you are good to go.

NOTE: Do not manually edit /etc/shadow file because it contains the encrypted password section which is automatically generated

# cat /etc/shadow | grep user

user:$6$HG.agA9Q$X2scLxur6G6FIW0eb1ArgAQcnioNLJmeBjDX.FAvfchXUhElwVKhwa3hHCFMI/vNUdr3fgqcge2PTEaKFfzXW/:16082::::::