|whoami||show which user is logged in|
|passwd||change password of current user|
|passwd jane||change Jane’s password|
|su||become superuser / change user to root|
|su jane||change user to jane|
|sudo||superuser do = do it as a superuser|
|adduser james||add a user named ‘james’|
|deluser james||delete the user ‘james’|
|passwd -l jane||lock jane’s password|
|passwd –lock jane||lock jane’s password|
shows which user is logged in
change the password for the current user.
passwd jane = Change Jane’s password
SuperUser. login to a different user, for example
su jalal = login to jalal’s account. only
su without a username provided will change to root user by default.
login to a different user, in this case root.
su root will both do the same thing.
add a user. for example,
adduser jane will add a user called jane. You need root/sudo access/permissions to cerate or delete a user.
delete a user. for example:
userdel jalal will delete the user named jalal. Use the
-r flag to delete the user BUT keep the user’s directory/files. For example:
userdel -r jalal will delete a user named jalal but keep his home directory and other files.
Locking a user’s password
passwd -l jane
The passwd command with the
--lock flag will lock the password of the named account (in our example, jane). Users with a locked password are not allowed to change their password.
Note that this does not disable the account. You need to be root (or have sudo priveleges) to be able to lock a user’s password.
Adding trusted sudo users
Sudo allows regular users to run commands as a super user. That way you won’t have to be running as root the whole time.
If you are on Ubuntu, sudo is already installed for you. If you are on Debian, you’ll have to install sudo:
apt-get install sudo
If the package is not found then you’ll have to update the system.
The above command will update our linux machine with all of the available source for apt-get.
Now that you have sudo installed, you’ll need to create/edit the
sudoers file. This file is located in the
cd /etc nano sudoers