Common Ubuntu Problems and their Solutions

-> Error: “E: Could not get lock /var/lib/apt/lists/lock – open (11:   Resource temporarily unavailable)”
        Solution: Change to root user and type the following commands -
             $ su
             # killall -9 apt-get aptitude
             # rm -f /var/lib/apt/lists/lock


         If you further get the same error, then type -
               # rm -f /var/lib/dpkg/lock


Restart Ubuntu GNOME session without Rebooting 

1. Press Ctrl+Alt+T to open the terminal.
2. Type the following command - $sudo /etc/init.d/gdm restart  

 Restore panels in Ubuntu to their default settings
1. Press Ctrl+Alt+T to open the terminal.
2. Type the following commands one by one in terminal
$ gconftool-2 --shutdown
$ gconftool --recursive-unset /apps/panel
$ rm -rf ~/.gconf/apps/panel
$ pkill gnome-panel


Auto Login for a specific user
1. Go to Users And Group settings and disable ask for password when login for that particular user.
2. The open terminal and go to  /etc/lightdm/lightdm.conf
3. Add the line  - 
        autologin-user=<username>
4. Save and exit.


Change Ip settings for Ubuntu server
1. sudo vi /etc/network/interfaces
2. For auto eth0 DHCP, add -
   auto eth0
   iface eth0 inet dhcp
3. For auto eth0 static IP, add -
    auto eth0
    iface eth0 inet static
        address 192.168.1.100
        netmask 255.255.255.0
        network 192.168.1.0
        broadcast 192.168.1.255
        gateway 192.168.1.1

4. Now add the DNS settings by editing resolv.conf file - 

    sudo vi /etc/resolv.conf

Installing Desktop environment on Ubuntu server

1. Update the repository -

     $ sudo apt-get update

2. If you want to install ubuntu desktop, type - 

     $ sudo apt-get install ubuntu-desktop

3. If you want to install desktop environment without addons like mail client or open office, type - 

     $ sudo aptitude install --without-recommends ubuntu-desktop

4. If you want to install some light weight desktop, type - 

     $ sudo apt-get install xubuntu-desktop

5. If you want to install the kde environment, type -

     $ sudo apt-get install kubuntu-desktop

Installing add-apt-repository
1. When you try to add repository on Ubuntu server, most often you get the error -
    sudo : add-apt-repository : command not found
2. The solution is to install python-software-properties
   sudo apt-get install python-software-properties