How to unmount while device is busy

Sometimes You might get the following error messages while unmounting
# umount /dev/sda2/
umount: /dev/sda2:device is busy
Try the below command
# fuser -m /dev/sda2
It will show the process id which is causing it
If you get the process id then you can umount!!!!!!

Fedora:How to restore deleted desktop panel

STEP 1:Make a directory
[antony@localhost ~]$ mkdir bak
STEP 2:Move the following files
[antony@localhost ~]$ mv {.gnome*,.gconf*} bak/
STEP 3:Reboot

Enable root login in GUI Fedora

STEP 1:Open the terminal and edit
vim /etc/pam.d/gdm
Comment the following line #auth required pam_succeed_if.so user != root quiet
STEP 2: Also Edit /etc/pam.d/gdm-password
Comment the following line #auth required pam_succeed_if.so user != root quiet
Done...

Disabling iptables in LINUX

For Fedora,Try the following commands
#service iptables save
# service iptables stop
# chkconfig iptables off
For other Linux distributions
# iptables -F
# iptables -X
# iptables -t nat -F
# iptables -t nat -X
# iptables -t mangle -F
# iptables -t mangle -X
# iptables -P INPUT ACCEPT
# iptables -P OUTPUT ACCEPT

Compiling Linux Kernel:Ubuntu

STEP 1: Download latest kernel from http://kernel.org
STEP 2:Extract the downloaded tar file
#tar -xvf linux-2.6.XXXX -C /usr/src#cd /usr/src
STEP 3:Configure Kernel
Make sure development tools "gcc compiler " got installed
#apt-get install gcc
Now type the following command and we can select different options as per our need#make menuconfig
STEP 4:Compilation of kernel
Initially create a compressed kernel image,
#make
Now start compiling to kernel modules
#make modules
Install kernel modules
#make modules_install
STEP 5:Install Kernel
#make install
The above command will install three files into /boot directory
->System.map-2.6.xx
->config-2.6.xx
->vmlinuz-2.6.xx
STEP 6:Creating initrd image
Create using following commands
# cd /boot# mkinitrd -o initrd.img-2.6.xx 2.6.xx
STEP 7:Modify Grub configuration file - /boot/grub/menu.lst
STEP 8:Update the grub
# update-grub
STEP 9:Reboot

Configuring Apache with SSL(WindowsXP)

Easy Steps to configure Apache with SSL
STEP1:
Install the following
i>jdk
ii>Apache Tomcat
STEP 2:
After installing the above softwares edit the following path,in System Variables
Go to,Mycomputer->RightClick->Prpoerties->Advanced->EnvironmentVariables->Under SystemVariables..Add the following variables
i>VariableName = classpath
VariableValue =c:\ProgramFiles\ApacheSoftwareFoundation\lib\servlet-api.jar
ii>VariableName = Path
VariableValue = c:\ProgramFiles\jdk*\bin
iii>VaribleName = JAVA_HOME
VariableValue = c:\ProgramFiles\Java\jdk*
iv>VariableName = CATALINA_HOME
VariableValue = c:\ProgramFiles\ApacheSoftwareFoundation\Tomcat*
STEP 3:
Now generate a key..
Open command prompt
c:\ProgarmFiles\Java\Jdk*\bin >keytool -genkey -alias Tomcat -keyalg RSA
It will prompt for keystore password :Enter any password and then foolow the instructions and finally enter yes and press enter.
Now a .keystore file will be generated in the user profile folder under c:\Document and settings\user
STEP 4:
Edit the server.xml file from the following location
c:\programFiles\ApacheSoftwareFoundation\Tomcat*\conf\Server.xml
Uncomment the line that starts with Connector = 8443
and also add the following
keystoreFile="Path were keystore file is generated"
keystorePass="Password that you entered while generating key"
STEP 5:
now start the apache web server and try
https://localhost:8443/

It should work

How to add a linux machine to Windows domain

This Article shows how to add a Ubuntu machine to Windows Domain
Here we are going to use a open source Tool (Likewise).
STEP1:
Install the package
#apt-get install likewise-open5
STEP 2:
Go to Terminal
#domainjoin-cli join domainname Administrator
Example: domainjoin-cli join antonysunny.com Administrator
In the above example domainname = antonysunny.com
It will prompt for Admin Password which has permission to join to domain
Make sure the system gets restarted
STEP 3:
Inorder to login Enter the username as domain\user
Example:ANTONYSUNNY\user
In the above example ANTONYSUNNY is the NETBIOS name for the domain name

Done
TROUBLESHOOTING:
->Inorder to make likewise-open use a default domain add the following to /etc/samba/lwiauthd.conf
winbind use default domain = yes
->Restart /etc/init.d/likewise-open restart
->Inorder to unjoin from domain Go to terminal
#domainjoin-cli leave