Change sudo default password cache | sudo’s default password cache time is 5 minutes. To change the default time, it is possible to edit a setting in /etc/sudoers as desired. I’ll show you how! Edit /etc/sudoers with your desired text editor, or as standard with sudo visudo: $ sudo visudo For example, to increase the timeout to 30 minutes for user
Suse | sudo asks for root password
Suse | sudo asks for root password | By default, the sudo command on Suse Linux asks for the root password instead of the user’s password. I’ll show you how to fix that to be more expected (and secure!) behavior of sudo and only ask for the user’s password. 1. Crack open a terminal, and issue: $ sudo visudo 2. Comment out the
Reset or Change User Password in Linux
Reset or Change User Password in Linux | To set or reset a user password in Linux, use the command passwd Here are some tips! When logged in as your regular account, simply type passwd at the command prompt to change your own password: scott@localhost:~$ passwd Changing password for scott (current) UNIX password: Enter new UNIX password: Retype new UNIX password: passwd: password
Prevent Postfix Brute Force
Prevent Postfix Brute Force | An often used attack vector is brute forcing MTA logins. While most admins watch ssh auth logs like a hawk, email auth/login logs are most often not closely watched for this sort of thing if at all. I’ll show you one way to easily prevent a Postfix brute force attack! This how-to focuses on fail2ban
Set Password Expiration for Linux Accounts
Set Password Expiration for Linux Accounts | For security, it is good to enforce password expiration. Here’s how you do it in Linux. Edit the file /etc/login.defs: sudo nano /etc/login.defs Here you can specify options for password expiration: PASS_MAX_DAYS 90 PASS_MIN_DAYS 7 PASS_MIN_LEN 14 PASS_WARN_AGE 7 Max Days: maximum life of a password Min Days: prevent a second change again for X
SSH Password Login From Specific IP Ranges
SSH Password Login From Specific IP Ranges | Want to require ssh keys from remote sources, but then allow ssh passwords from your local home network? It is easy to make this specific configuration or alter as desired for your server. I’ll show you how! 1. Edit the sshd_config file sudo nano /etc/ssh/sshd_config In this file, edit the existing line PasswordAuthentication to ‘no’
Generate Strong Passwords
Generate Strong Passwords | How can I generate strong passwords from the command line? The excellent program apg is fantastic for generating all sorts of passwords. 1. Install apg: $ sudo apt-get install apg 2. Then you can simply run $ apg …which will run default options and give something like this: stmiller@li166-66:~$ apg Please enter some random data
Thunderbird Recover Email Password
Thunderbird Recover Email Password | How do I recover saved passwords from Thunderbird? Finding saved email passwords in Thunderbird is as easy as going to the Security portion of the settings: Tools -> Options (Windows) | Edit -> Preferences (Linux) | Thunderbird -> Preferences (OS X) -> Security > Passwords > Saved Passwords There you are given an option to
How to create a user in Linux
How to create a user in Linux | How do I create a user in Linux? The old school way is to use the command useradd. Do this command to add user jsmith with a home directory: sudo useradd -d /home/jsmith -s /bin/bash -m jsmith Set the password for user jsmith by then issuing: sudo passwd jsmith It will then prompt you to
