I know how to open .rar file under Linux, but how do you open .rar file under Apple OS X UNIX using command line and GUI tools options?
Q. I donâ€™t need GUI as Iâ€™m developing CLI based applications. By default Ubuntu Loads Gnome GUI. How do I disable X.org / Gnome under Linux so that I get text only login?
A. You can use GUI tools or command line tools to disable GDM (Gnome Display Manager) service (/etc/init.d/gdm).
Disable GDM using GUI tools
The Services Administration Tool allows you to specify which services will be started during the system boot process. You can type the command:
Or just click on System > Administration > Services
Now you will be prompted for the administrator password, this is necessary because the changes done with this tool will affect the whole system. After entering the administrator password, the following window is displayed:
Make sure you remove GDM (Gnome login manager) by disabling the the checkbox and close the window.
Enable GDM using Command Line (CLI) tools
Ubuntu comes with rcconf and update-rc.d command. rcconf allows you to control which services are started when the system boots up or reboots. It displays a menu of all the services which could be started at boot. The ones that are configured to do so are marked and you can toggle individual services on and off.
Use apt-get command:
sudo apt-get install rcconf
Now start rcconf:
Again you will be prompted for the administrator password, this is necessary because the changes done with this tool will affect the whole system. After entering the administrator password, the following text based window is displayed on screen:
Next enable GDM service by pressing space bar (check the checkbox) > Click OK to save the changes.
This is 3rd and old method. You can enable or disable any service using update-rc.d command.
Task: Disable X.org GUI
Just enter command:
sudo update-rc.d -f gdm remove
Task: Enable X.org GUI
Just enter command:
sudo update-rc.d -f gdm defaults
You can always start GUI from a shell prompt by typing startx command:
Please note that you can use above tools to enable or disable any services under Debian / Ubuntu Linux.
Q. How do I change ip address in Linux?
A. There are different ways to change IP address in Linux
(a) Command Line tools
(b) Modify configuration files
(c) Use GUI tools
Task: Display current IP address and setting for network interface called eth0
Use ifconfig command:
# ifconfig eth0
eth0 Link encap:Ethernet HWaddr 00:30:48:5A:BF:46 inet addr:10.5.123.2 Bcast:10.5.123.63 Mask:255.255.255.192 inet6 addr: fe80::230:48ff:fe5a:bf46/64 Scope:Link UP BROADCAST RUNNING MULTICAST MTU:1500 Metric:1 RX packets:728204 errors:0 dropped:0 overruns:0 frame:0 TX packets:1097451 errors:0 dropped:0 overruns:0 carrier:0 collisions:0 txqueuelen:1000 RX bytes:62774749 (59.8 MiB) TX bytes:1584343634 (1.4 GiB) Interrupt:177
Task: Change IP address
You can change ip address using ifconfig command itself. To set IP address 192.168.1.5, enter command:
# ifconfig eth0 192.168.1.5 netmask 255.255.255.0 up
# ifconfig eth0
To make permanent changes to IP address you need to edit configuration file according to your Linux distribution.
Change IP address under RedHat / CentOS / Fedora core Linux
=> Please read – Howto change and setup IP address in Redhat Linux
Change IP address under Debian / Ubuntu Linux
I need to disable firewall in Linux for testing purpose. I’m using CentOS and RHEL version 4.4 / 5 / 6. How do I disable the firewall in Linux?