1. Stop MySql server using following command.

$ sudo /etc/init.d/mysql stop

2. Copy the existing data directory (which is located in /var/lib/mysql) using following command.

$ sudo cp -R -p /var/lib/mysql /path/to/new/datadir

3. Edit the MySQL configuration file with your favorite text editor.

$ sudo vim /etc/mysql/my.cnf

4. Find the entry for datadir, change the path to the new data directory.
5. Some Linux distributions uses some security software called AppArmor that specifies the areas of your filesystem applications are allowed to access. Unless you modify the AppArmor profile for MySQL, you’ll never be able to restart MySQL with the new datadir location. So edit the file /etc/apparmor.d/usr.sbin.mysqld using your favorite editor.

$ sudo vim /etc/apparmor.d/usr.sbin.mysqld

6. Duplicate the lines beginning with /var/lib/mysql and replace duplicated strings with /new_datadir.

/var/lib/mysql/ r,
/var/lib/mysql/** rwk,
/var/log/mysql/ r,
/var/log/mysql/* rw,
#
/path/to/new/datadir r,
/path/to/new/datadir** rwk,
/path/to/new/datadir r,
/path/to/new/datadir* rw,

7. Restart the AppArmor profiles with the following command.

$ sudo /etc/init.d/apparmor restart

8. Restart the MySql server with the following command.

$ sudo /etc/init.d/mysql start

MySQL should now start without any errors and your data will be stored in the new location.

1. Create a Firewall script

 vim /etc/set_iptables.bash

echo 1 > /proc/sys/net/ipv4/ip_forward

iptables -t nat -A POSTROUTING -o eth0 -j MASQUERADE
iptables -t nat -A PREROUTING -p tcp -i eth0 -d 192.168.0.10 --dport 555 -j DNAT --to 192.168.0.12:22
iptables -A FORWARD -p tcp -i eth0 -d 192.168.0.12 --dport 22 -j ACCEPT

2. Change the file permission mod

sudo chmod o+x /etc/set_iptables.bash

3. Create a start.stop script

vim /etc/init.d/iptables

#!/bin/bash

RETVAL=0

# To start the firewall
start() {
  echo -n "Iptables rules creation: "
  /etc/set_iptables.bash
  RETVAL=0
}

# To stop the firewall
stop() {
  echo -n "Removing all iptables rules: "
  /sbin/iptables -F
  RETVAL=0
}

case $1 in
  start)
    start
    ;;
  stop)
    stop
    ;;
  restart)
    stop
    start
    ;;
  status)
    /sbin/iptables -L
    /sbin/iptables -t nat -L
    RETVAL=0
    ;;
  *)
    echo "Usage: iptables {start|stop|restart|status}"
    RETVAL=1
esac
exit

4. Change the file permission mod

sudo chmod o+x /etc/init.d/iptables

5. The final step is to make your script running on each boot of your computer:

sudo update-rc.d iptables defaults

Now you can use these commands to start/stop/restart/status your iptables.

sudo /etc/init.d/iptables start
sudo /etc/init.d/iptables stop
sudo /etc/init.d/iptables restart
sudo /etc/init.d/iptables status

ufw is stands for Uncomplicated Firewall, this program is for managing a Linux firewall and aims to provide an easy to use interface for the user, as well as support package integration and dynamic-detection of open ports. ufw  is not intended to provide complete firewall functionality via its command interface, but instead provides an easy way to  add  or  remove simple rules. It is currently mainly used for host-based firewalls.

Installation

$ sudo apt-get install ufw

For help use

$ man ufw

To enable firewall

$ sudo ufw enable

When we enable the firewall it will set firewall with default settings, it will deny ssh ports, telnet and many other services. So when we enable firewall on the remort servers we must enable ssh ports first, this can done using.

$ ufw allow proto tcp from any to any port 22

To disable a firewall

$ sudo sfw disable

Examples

Deny all access to port 53:

$ sudo ufw deny 53

Allow all access to tcp port 80:

$ sudo ufw allow 80/tcp

Allow all access from RFC1918 networks to this host:

$ sudo ufw allow from 10.0.0.0/8
$ sudo ufw allow from 172.16.0.0/12
$ sudo ufw allow from 192.168.0.0/16

Deny access to udp port 514 from host 1.2.3.4:

$ sudo ufw deny proto udp from 1.2.3.4 to any port 514

Allow access to udp 1.2.3.4 port 5469 from 1.2.3.5 port 5469:

$ sudo ufw allow proto udp from 1.2.3.5 port 5469 to 1.2.3.4 port 5469

First method is to use  set req.http.host and set req.url in the vcl.conf file. Using these two methods we perform normal redirection. Using these method we will redirect the url to some other URL on the same host. For example say the URL http://example.com/error500.php will be redirect to the URL http://example.com/redirect.php. We specify 301/302 redirection to the URL http://foo.com/index.php in the redirect.php file using header method.

• In the sub vcl_recv method use the following code.

sub vcl_recv {
   if (req.http.host ~ "example.com") {
      if (req.url ~ "error500.php") {
         set req.http.host = "example.com";
         set req.url = "/redirect.php";
      }
   }
}

• In the redirect.php file use the following method.

<?php
header("HTTP/1.1 302 Moved Temperarly");
header('Location:http://foo.com/index.php');
exit;
?>

Second method is to use vcl_error error method. In this error method we can specify HTML tags, so using meta tags we can implement redirection. This option is available with the latest version of varnish.

• In the sub vcl_recv method use the following code.

sub vcl_recv {
   if (req.http.host ~ "example.com") {
      if (req.url ~ "error500.php")
         error;
      }
   }
}
sub vcl_error {
        set obj.http.Content-Type = "text/html; charset=utf-8";
        if (req.http.host ~ "example.com") {
                if (req.url ~ "error500.php") {
                        synthetic {"
                                <?xml version="1.0" encoding="utf-8"?>
                                <!DOCTYPE html PUBLIC "-//W3C//DTD XHTML 1.0 Strict//EN" "http://www.w3.org/TR/xhtml1/DTD/xhtml1-strict.dtd">
                                <html>
                                        <head>
                                                <meta http-equiv="refresh" content="0;url=http://foo.com/index.php">
                                        </head>
                                </html>
                        "};
                }
        }
        deliver;
}

OpenNTPD is a Unix system daemon implementing the Network Time Protocol to synchronize the local clock of a computer system with remote NTP servers.

OpenNTPD is primarily developed by Henning Brauer as part of the OpenBSD project. Its design goals include being secure (non-exploitable), easy to configure, accurate enough for most purposes and with source code that can be distributed under a BSD license.

This tool helped me a lot. Using openntpd we can set the same time on multiple system.

Installation

$ sudo apt-get install openntpd

Openntp configuration file /etc/openntpd/ntpd.conf

To set the time use the command ntpdate-debian

$ sudo ntpdate-debian
[sudo] password for shahid:
 7 Aug 00:20:33 ntpdate[26597]: adjust time server 59.165.131.82 offset -0.089443 sec

When screen is called, it creates a single window with a  shell  in  it and then gets out of your way so that you can use the program as you normally would.  Then, at any time, you  can create new windows with other programs in them (including more shells), kill existing windows, view a list of windows, turn  output  logging  on and off, copy-and-paste text between windows, view the scroll back history, switch between windows in whatever manner you wish, etc.  All  windows  run  their  programs completely independent of each other.  Programs continue to run when their window is currently not visible and even when the whole screen session is detached from the user’s terminal.  When a program terminates, screen (per  default)  kills  the window  that  contained  it.  If this window was in the foreground, the display switches to the previous  window;  if  none  are  left,  screen exits.

 Usage

To start screen us the command screen.

$ screen

In the virtual terminal you can start any applications as you normaly done in normal terminals. Even if you close the virtual terminal the application will continue running in the back ground.

To list how many screens where on use the following command.

$ screen -ls
There are screens on:
        6475.pts-8.user-desktop        (Attached)
        6400.pts-6.user-desktop        (Attached)
2 Sockets in /var/run/screen/S-user.

To reattaches a screen session use the following command.

$ screen -d -r 6400.pts-6.user-desktop

To removed the distroyed sessions use the following command.

 $ screen -wipe

Installing Cursor, GTK and Icon Theme

To install cursor,gtk and icon theme first download the package from the link given below :

http://rapidshare.de/files/38210507/MyTheme.tar.gz.html

To install the theme package we have downloaded fro the above link, go to (System -> Preferences -> Appearance) and click Install and point to our newly downloaded Mytheme.tar.gz archive.

This should start installing the theme package (Cursors/Icons/Theme) once installation is completed . Chose Customize in theme and click on Customize.

In this window in Icons chose LeopardX , in Controls Mac4Lin_GTK_Aqua_v0.3 , in Window Border Mac4Lin_GTK_Aqua_v0.3 and in Pointers White Cursor .

If you have followed the steps properly the theme and icons should have been installed , and you should be able to see the new theme applied to your default desktop.

Enabling Compiz Graphic Effects and installing Mac$lin Theme

First Step is to install compiconf-settings-managerusing apt-get

shahid@shahid-laptop:~$ sudo apt-get install compizconfig-settings-manager

Before customizing Compiz you have to change Appearance Preference to Extra ( System -> Preferences -> Appearence )

After completing above steps , you can customize compiz by going to System -> Preferences -> Advanced Desktop Effects Settings .

After this Install Emerald Theme Manager using apt-get

shahid@shahid-laptop:~$ sudo apt-get install emerald

After installation is over download MacOS X Emerald theme from this link : http://gnome-look.org/content/show.php/Mac4Lin+Leopard+Emerald+Theme?content=68409

Now open (System -> Preferences -> Emerald Theme Manager )

After Emerald theme manager opens click on import and point to the downloaded theme package from withing the Theme Manager , you will find Mac4Lin Theme listed select the theme , click on refresh and quit the application

Mav like Dock with Avant Navigator

After the above steps Install Avant Window Navigator.

Avant Windows Navigator is cool little tool that allows you to have a cute looking dock at the bottom of the screen . Even though AWN is still very buggy, still because it is so feature rich and cool looking you could install it .

To install AWN you need to add extra repositories, now adding any additional repository carries certain amount of risk of screwing up your system so follow these step at your own risk.

To add repository:

shahid@shahid-laptop:~$ echo "deb  http://ppa.launchpad.net/awn-testing/ubuntu hardy main" | sudo tee -a /etc/apt/sources.list
shahid@shahid-laptop:~$ echo "deb-src http://ppa.launchpad.net/awn-testing/ubuntu hardy main" | sudo tee -a /etc/apt/sources.list

After issuing above command type the following command to update your repositories :

shahid@shahid-laptop:~$ sudo apt-get update

and finally to install AWN issue the following command in the terminal window :

shahid@shahid-laptop:~$ sudo apt-get install awn-manager-trunk awn-extras-applets-trunk

Now after completing above mentioned steps AWN should be properly installed , To Launch AWN go to (Applications -> Accessories -> Avant Window Navigator )
Now you could customize AWN by choosing to add more applets , configuring 3D effects for AWN etc by going to AWN Manager ( System -> Preferences -> Awn Manager )

Though the theme which AWN comes with preinstalled is also good , you might like to try this it’s cool and very Mac like
http://rapidshare.com/files/71511920/Transparent.tgz.html
you could install this theme through AWN Manager go to (System->Preferences->AWN manager) and go to themes there and click on “Add” and point it to the downloaded theme.

You will see a confirmation dialog box that theme has been added properly. Close AWN Manager and start it again and chose the theme just installed and press apply button to make this theme default theme of AWN.
This is how my AWN Dock looks(with the above theme installed) like : -

1. First thing to do is add the [third-party] fprint repository to your sources file ‘/etc/apt/sources.list'

# Fingerprint reader support (fprint)
deb http://ppa.launchpad.net/madman2k/ubuntu hardy main restricted universe multiverse

2. Next, update your sources and install fprint:

$sudo apt-get update
sudo apt-get install fprint-demo libfprint-dev libfprint0 libpam-fprint

3. Now you can enroll your fingers using either the terminal or a graphical user interface.
Terminal:

$ pam_fprint_enroll

GUI:

$ fprint_demo

4. Last thing to do is configure PAM so that the fingerprint reader can be useful. Open up your PAM authentication file and edit it:

$ sudo gedit /etc/pam.d/common-auth

5. Edit it to contain:

$ auth sufficient pam_fprint.so
$ auth required pam_unix.so nullok_secure

Enjoy your Fingerprint Reader Support

Steps 4 and 5 tell Ubuntu to check your fingerprint, and if that fails, then ask your password. This rule has some exceptions, one that I have encountered is on the login screen. I have to scan my fingerprint before typing my password. One thing I did notice is that when you use sudo in the terminal, it asks for your fingerprint, which I thought was pretty cool. One disadvantage is that anything using gksu does not seem to work properly, specifically because it does not tell you to scan your finger when needed.

Here is the details of what did to get the webcam running on using Ubuntu.

$ svn checkout http://svn.berlios.de/svnroot/repos/linux-uvc/
$ cd linux-uvc/linux-uvc/trunk/
$ make
$ sudo make install
$ modprobe uvcvideo

Tested with ‘ekiga ‘ and ‘xawtv’