Using YUM in RHEL, CentOS, Fedora

The following article will describe how to use YUM in RHEL, CentOS and Fedora.

http://tinyurl.com/8la63w

Installing Ubuntu 8.04 and Fedora 9

These tutorials will give you a idea how to install and configure Ubuntu 8.04 and Fedora 9 as both Desktops and Servers.

The Perfect Desktop - Ubuntu 8.04 LTS (Hardy Heron)

The Perfect Desktop - Fedora 9

The Perfect Server - Ubuntu Hardy Heron (Ubuntu 8.04 LTS Server)

The Perfect Server - Fedora 9

All credits goes to the authors of the above tutorials Falko Timme and Oliver Meyer

Linux Unerace Undelete Command

This is a tutorial explaining how to undelete data in Linux

http://tiny.cc/tMJGW

As explained above, We can't undelete or unerace files in Linux, But try out the following live Linux distributions, These are used for system rescue operations.

Trinity Rescue Kit - Website
SystemRescueCd - Website

26/03/2008 - I found this article on how to undelete files form ext3 file system, interesting..

Finding All Hosts on a Network

This is nice little script to find out all hosts in a Linux or a Windows network

http://tiny.cc/aYs2h

Using YUM and RPM in RedHat / Fedora / CentOS

This is a guide to learn all the things about RPM (Red Hat Package Manager)

http://docs.fedoraproject.org/drafts/rpm-guide-en

This is a guide to learn all the things about YUM (Yellow dog Updater, Modified)

http://docs.fedoraproject.org/yum/en

Enabling Compiz Fusion on Fedora

Read this tutorial to learn how to enable compiz fusion on Fedora

http://www.howtoforge.com/compiz-fusion-fedora8-nvidia-geforce-fx-5200-p2

Adding Cron Jobs in Linux (Schedule Tasks)

Tutorial about adding cron jobs in Linux (schedule tasks)

http://tiny.cc/DsJr7

Removing Users From Groups In CentOS / RHEL / Fedora

Removing Users From Groups In CentOS / RHEL / Fedora In CLI

So many websites will explain how to add a user to a group, but if i need to remove a user from a group in the CLI how to do it, This is how..

If you don't know how to add a user to a group read the following tutorial.

http://tiny.cc/W0bzu

How to remove a user from a group.

I have not found any commands for this so I'll teach a manual method.

Assume there is a group call "group1" and there are three members in the group call "user1", "user2", "user3"

I want to remove "user2" from "group1"

1. The group details will be stored under two files call "group" and another call "gshadow", We'll examine the files first

# cat /etc/group

You'll find a line as follows

group1:x:503:user1,user2,user3

# cat /etc/gshadow

You'll find a line as follows

group1:!::user1,user2,user3

2. Now what we have to do is, manually remove "user2" from the "group1", Give the following command.

# vigr

The above command will open "/etc/group" file in VI text editor.

3. Use the down arrow key and go up to "group1:x:503:user1,user2,user3" line and press " i " to go to insert mode, and delete "user2" from the line, Now it'll look like this.

group1:x:503:user1,user3

Then press "esc" and type" :wq " to save and exit the file. It'll ask a question as follows,

You are using shadow groups on this system.
Would you like to edit /etc/gshadow now [y/n]?

Press " y " and press "enter"

Now it'll open "/etc/gshadow" file in VI text editor.

Use the down arrow key and go up to "group1:!::user1,user2,user3" line and press " i " to go to insert mode, and delete "user2" from the line, Now it'll look like this.

group1:!::user1,user3

Then press "esc" and type" :wq " to save and exit the file.

4. That's it, now the "user2" is removed from "group1"

This is another way to do it but you want be able to completely remove a user from the groups he/she belong to.

http://tiny.cc/zMm7x

Controlling Services In Linux

In a Linux box lot of services will be started during the startup, but we may not need all the services automatically getting started. We can turn off the unwanted services and make our system faster.

1. Read the following tutorial and get an idea about Linux services, although it's written for fedora, all these services will be similar in all Linux systems.

http://www.mjmwired.net/resources/mjm-services-f8.html

2. Controlling

In Ubuntu, RedHat, Fedora, CentOS (GUI)

Go to System -> Administration -> Services -> Unselect unwanted services

In Redhat, Fedora, CentOS (CLI)

# chkconfig servicename off

If you want to turn the service on again

# chkconfig servicename on

Or type

# ntsysv

And using the space bar you can select or unselect the services.

A Cool Fedora Story

You have to read this, It's a story about how to contribute software packages in to Fedora project. Fedora is the community OS release of RHEL.

http://www.redhatmagazine.com/2008/02/28/when-sally-met-eddie-the-fedora-package-story

Installing Adobe Flash Plugin for Firefox in Redhat / CentOS / Fedora

For 32 bit users

1. Go to Adobe Flash Plugin web site, Follow the instructions under option 3 " YUM REPOSITORY INSTALLATION"

Web site - http://www.adobe.com/shockwave/download/download.cgi?P1_Prod_Version=ShockwaveFlash

For 64 bit users

1. Install the nspluginwrapper.i386 package to enable the 32-bit Adobe Flash plugin in x86_64 Firefox and the pulseaudio-libs.i386 package to enable sound from the plugin.

2. Create the 32bit mozilla plugin directory using this command.

# mkdir -p /usr/lib/mozilla/plugins

3. Install the nspluginwrapper.i386, nspluginwrapper.x86_64, and pulseaudio-libs.i386 packages.

# yum -y install nspluginwrapper.{i386,x86_64} pulseaudio-libs.i386

4. Install flash-plugin as shown in 32 bit section above.

5. Run mozilla-plugin-config to register the flash plugin.

# mozilla-plugin-config -i -g -v

6. Close all Firefox windows, and then relaunch Firefox.

7. Type about:plugins in the URL bar to ensure the plugin is loaded.

NOTE - The following was adapted from the Fedora 8 Release Notes. The 64 bit instructions may NOT work for RHEL 5 and CentOS 5.

Special Thanks to Fedora Documentation Team and Mauriat Miranda

Ubuntu Desktop Customization Guide

A nice customization guide about how to make your GNOME desktop beautiful, although written targeting Ubuntu most parts of the tutorial will be valid for any Linux distribution using GNOME.

http://tuxenclave.wordpress.com/2007/11/23/ubuntu-customization-guide-v2

Microsoft fonts for Fedora/Redhat/Centos

Download Microsoft core fonts RPM that includes fonts in XP/Vista

http://avi.alkalay.net/software/webcore-fonts

Custom GRUB splash image in Fedora/Redhat/Centos

• Log or Switch in to the root account

• Get an image file to use for the new splash image (can be some wallpaper in jpg, png format)
  

• Check whether ImageMagick rpm is installed

# rpm -q ImageMagick

• If it's not installed you have to install it first

# yum -y install ImageMagick

• Then, Assuming the image is in the root's home folder & the image name is "myboot.jpg"

# cd
# convert myboot.jpg -resize 640x480! -colors 14 -depth 8 myboot.xpm
# ls

• Now you will be able to see a file call "myboot.xpm"

• Then you have to gzip it.

# gzip myboot.xpm
# ls

• Now you will be able to see a file call "myboot.xpm.gz"

• Then you have to copy it to "/boot/grub" folder

# cp myboot.xpm.gz /boot/grub

• Then you have to edit "grub.conf" file with your favorite text editor, I'll use "nano" text editor

# nano /etc/grub.conf

Edit the following line

splashimage=(hd0,0)/grub/splash.xpm.gz

to

splashimage=(hd0,0)/grub/myboot.xpm.gz

NOTE- DON'T EDIT ANYOTHER PARAMETER OF THE LINE, ONLY CHANGE THE IMAGE FILE NAME.

save & exit

• Then reboot your system

# reboot

• Then you'll be able to see the new GRUB spalsh image during the startup.

Sinhala fonts for Ubuntu and Fedora

By default in Fedora Sinhalese is inbuilt, during the Fedora installation you can select it as a additional language but for Ubuntu go to http://sinhala.sourceforge.net and follow the instructions there.