How to Setup Two-Factor Authentication (Google Authenticator) for SSH Logins

From Techmint.com By default, SSH already uses a secure data communication between remote machines, but if you want to add some extra security layer to your SSH connections, you can add a Google Authenticator (two-factor authentication) module that allow you to enter a random one-time password (TOTP) verification code while connecting to SSH servers. You’ll have to enter the verification code from your smartphone or PC when you...

How To Grant A User The Power Commands?

Change what the user can invoke a command. Dijae ALL=(ALL) NOPASSWD: ALL this will make the user Dijae invoke a root command without typing first sudo on every folder he wants to. Manual: NAME visudo - edit the sudoers file  SYNOPSIS visudo [ -c ] [ -f sudoers ] [ -q ] [ -s ] [ -V ] ...

Incremental Backup with TAR

We often use TAR to backup files to tape to make full backup or using ctime or atime for creating new file names. But while your files are getting larger, let's say apache, logs or any file that modifies from time to time you need to have incremental backups. Incremental backups let's you backup only the files/folder that...

Check The Exact Capacity of Your Database

If you want to know the exact capacity of your database. Check this! Image from: findicons.com 1. SQL script Sum up the data_length + index_length is equal to the total table size. data_length – store the real data. index_length – store the table index. Here’s the SQL script to list out the entire databases size SELECT table_schema "Data...

Useful Uses of YUM

This link gives you techniques in using YUM. http://www.tecmint.com/20-linux-yum-yellowdog-updater-modified-commands-for-package-mangement/ What is YUM? YUM (Yellowdog Updater Modified) is an open source command-line as well as graphical based package management tool for RPM (RedHat Package Manager) based Linux systems. It allows users and system administrator to easily install, update, remove or search software packages on a systems. It was developed and released by Seth...

How To Display Date And Time In "Oct 14, 2013 14:22:59" Format?

How to display date and time format like "Oct 14, 2013 14:21:59". date +"%b %d, %Y %H:%M:%S" This is useful in making a time stamp of your logs. ...

Helpful Administration Linx

Yolinux http://www.yolinux.com/TUTORIALS/ This is a very good guide for administering your linux servers, also there are tutorials and other links possible for downloads and other related guides. Adding Users and After http://serverfault.com/questions/63764/create-home-directories-after-create-users You will need to create the users directory manually. This requires three steps: Create directory in compliance to /etc/passwd, usually there will be already a /home/login entry....