First sign on or “su” or “sudo” to the “root” account on Linux, run: sudo -i.
Then type, passwd tom to change a password for tom user.
The system will prompt you to enter a password twice.
Hereof, how do I change my password in Unix Putty? How to Change the Password in Putty
Launch Putty. ...
Click the "SSH" radio button below the host name text box. ...
Click the "Open" button at the bottom of the dialog box. ...
Enter your current user name and password when prompted. ...
Type the command "Passwd" after you've logged in. ...
Type in your old password and press "Enter."
Really, how can I reset my Linux password?
If you realize that you have forgotten your pasword while logged in, you can create a new one for yourself. Open a shell prompt and enter the command passwd. The passwd command asks for the new password, which you will have to enter twice. The next time you log in, use the new password.
How do I change my root password?
Resetting the Root Password
Log in to the server with the root user using your existing password.
Now, to change the password for the root user, enter the command: passwd root.
On the new password prompt, provide the new password a couple of times and then hit enter.
Unsourced material may be challenged and removed. passwd is a command on Unix, Plan 9, Inferno, and most Unix-like operating systems used to change a user's password. The password entered by the user is run through a key derivation function to create a hashed version of the new password, which is saved.
To change to a different user and create a session as if the other user had logged in from a command prompt, type "su -" followed by a space and the target user's username. Type the target user's password when prompted.
passwd command in Linux is used to change the user account passwords. The root user reserves the privilege to change the password for any user on the system, while a normal user can only change the account password for his or her own account.
To force a user to change his/her password, first of all the password must have expired and to cause a user's password to expire, you can use the passwd command, which is used to change a user's password by specifying the -e or --expire switch along with username as shown.
If You Haven't Logged In: You should always change an old password that hasn't been used in over a year, but some experts recommend changing old passwords after just a few months. The more often you change slightly-used passwords, the safer you'll be; especially if you're not using multi-factor authentication.
Press the ctrl-alt-del keys all at the same time on your computer keyboard. Choose the Change Password option that appears on the screen. The Change Password dialog box will appear. Enter your current password, along with your new password twice.
Unix Usernames. The username is an identifier: it tells the computer who you are. In contrast, a password is an authenticator: you use it to prove to the operating system that you are who you claim to be. A single person can have more than one Unix account on the same computer.
Creating a key pair In the PuTTY Key Generator box, make sure the radio button at the bottom is selected for RSA. Click the Generate button. Move your mouse around the box to help generate the keys. On the bottom right, there are buttons named Save public key and Save private key – save both to your computer.
Press Ctrl+C or right-click the highlighted text and then left-click on Copy in the context menu. Position the cursor in PuTTY where you want to paste the copied text from Windows, then right-click to paste it or press Shift + Insert.
The chage command is self-described as the "change user password expiry information" utility. ... The chage command changes the number of days between password changes and the date of the last password change. This information is used by the system to determine when a user must change their password.