Ubuntu server Installing Guide and Tutorial

Here you can find information on how to install and configure various server applications. It is a stepby step, task-oriented guide for configuring and customizing your system. This guide assumes you have a basic understanding of your Ubuntu system. Some installation details are covered in Part II, Installation [p. 3], but if you need detailed instructions installing Ubuntu please refer to the Ubuntu Installation Guide.

A HTML version of the manual is available online at the Ubuntu Documentation website. The
HTML files are also available in the ubuntu-serverguide package. See Part II, Package Management [p. 17] for details on installing packages.

If you choose to install the ubuntu-serverguide you can view this document from a console by:

w3m /usr/share/ubuntu-serverguide/html/C/index.html

If you are using a localized version of Ubuntu, replace C with your language localization (e.g. en_GB).

Support
There are a couple of different ways that Ubuntu Server Edition is supported, commercial support and community support. The main commercial support (and development funding) is available from Canonical Ltd. They supply reasonably priced support contracts on a per desktop or per server basis. For more information see the Canonical Services page.

Installation

This chapter provides a quick overview of installing Ubuntu 10.04 LTS Server Edition. For more
detailed instructions, please refer to the Ubuntu Installation Guide.  Community support is also provided by dedicated individuals, and companies, that wish to make Ubuntu the best distribution possible. Support is provided through multiple mailing lists, IRC channels, forums, blogs, wikis, etc. The large amount of information available can be overwhelming, but a good search engine query can usually provide an answer to your questions. See the Ubuntu Support4 page for more information.

1. Preparing to Install

This section explains various aspects to consider before starting the installation.

1.1. System Requirements

Ubuntu 10.04 LTS Server Edition supports two (2) major architectures: Intel x86 and AMD64. The table below lists recommended hardware specifications. Depending on your needs, you might manage with less than this. However, most users risk being frustrated if they ignore these suggestions.

Recommended Minimum Requirements

Install Type RAM Base Hard Drive Space All Tasks Installed System

Server 128 megabytes Hard Drive Space 500 megabytes-1 gigabyte

The Server Edition provides a common base for all sorts of server applications. It is a minimalist
design providing a platform for the desired services, such as file/print services, web hosting, email hosting, etc.

1.2. Server and Desktop Differences

There are a few differences between the Ubuntu Server Edition and the Ubuntu Desktop Edition. It should be noted that both editions use the same apt repositories. Making it just as easy to install a server application on the Desktop Edition as it is on the Server Edition. The differences between the two editions are the lack of an X window environment in the Server Edition, the installation process, and different Kernel options.

1.2.1. Kernel Differences:

• The Server Edition uses the Deadline I/O scheduler instead of the CFQ scheduler used by the
Desktop Edition.
• Preemption is turned off in the Server Edition.
• The timer interrupt is 100 Hz in the Server Edition and 250 Hz in the Desktop Edition.

When running a 64-bit version of Ubuntu on 64-bit processors you are not limited by memory addressing space.

To see all kernel configuration options you can look through /boot/config-2.6.31-server. Also, Linux Kernel in a Nutshell2 is a great resource on the options available.

1.3. Backing Up
• Before installing Ubuntu Server Edition you should make sure all data on the system is backed up. See read continue , Backups [p. 240] for backup options.

If this is not the first time an operating system has been installed on your computer, it is likely you will need to re-partition your disk to make room for Ubuntu.

Any time you partition your disk, you should be prepared to lose everything on the disk should you make a mistake or something goes wrong during partitioning. The programs used in installation are quite reliable, most have seen years of use, but they also perform destructive actions.

2. Installing from CD

The basic steps to install Ubuntu Server Edition from CD are the same for installing any operating system from CD. Unlike the Desktop Edition the Server Edition does not include a graphical installation program. Instead the Server Edition uses a console menu based process.
• First, download and burn the appropriate ISO file from the Ubuntu web site3.
• Boot the system from the CD-ROM drive.
• At the boot prompt you will be asked to select the language. Afterwards the installation process
begins by asking for your keyboard layout.
• From the main boot menu there are some additional options to install Ubuntu Server Edition. You can install a basic Ubuntu Server, or install Ubuntu Server as part of a Ubuntu Enterprise Cloud. For more information on UEC see Section 3, “UEC” [p. 269]. The rest of this section will cover the basic Ubuntu Server install.
• The installer then discovers your hardware configuration, and configures the network settings using DHCP. If you do not wish to use DHCP at the next screen choose "Go Back", and you have the option to "Configure the network manually".
• Next, the installer asks for the system's hostname and Time Zone.• You can then choose from several options to configure the hard drive layout. For advanced disk options see Section, “Advanced Installation” [p. 10].
• The Ubuntu base system is then installed.• A new user is setup, this user will have root access through the sudo utility.
• After the user is setup, you will be asked to encrypt your home directory.• The next step in the installation process is to decide how you want to update the system. There are three options:
• No automatic updates: this requires an administrator to log into the machine and manually install updates.• Install security updates Automatically: will install the unattended-upgrades package, which
will install security updates without the intervention of an administrator. For more details see
Section 5, “Automatic Updates”.
• Manage the system with Landscape: Landscape is a paid service provided by Canonical to help
manage your Ubuntu machines. See the Landscape4 site for details.
• You now have the option to install, or not install, several package tasks. See Section 2.1, “Package Tasks” [p. 7] for details. Also, there is an option to launch aptitude to choose specific
packages to install. For more information see Section 4, “Aptitude” [p. 22].
• Finally, the last step before rebooting is to set the clock to UTC.

If at any point during installation you are not satisfied by the default setting, use the "Go Back" function at any prompt to be brought to a detailed installation menu that will allow you to modify the default settings.

At some point during the installation process you may want to read the help screen provided by the
installation system. To do this, press F1.

Once again, for detailed instructions see the Ubuntu Installation Guide

2.1. Package Tasks

During the Server Edition installation you have the option of installing additional packages from the CD. The packages are grouped by the type of service they provide.

• Cloud computing: Walrus storage service
• Cloud computing: all-in-one cluster
• Cloud computing: Cluster controller
• Cloud computing: Node controller
• Cloud computing: Storage controller
• Cloud computing: top-level cloud controller
• DNS server: Selects the BIND DNS server and its documentation.
• LAMP server: Selects a ready-made Linux/Apache/MySQL/PHP server.
• Mail server: This task selects a variety of package useful for a general purpose mail server system.
• OpenSSH server: Selects packages needed for an OpenSSH server.
• PostgreSQL database: This task selects client and server packages for the PostgreSQL database.
• Print server: This task sets up your system to be a print server.
• Samba File server: This task sets up your system to be a Samba file server, which is especially
suitable in networks with both Windows and Linux systems.
• Tomcat server: Installs the Apache Tomcat and needed dependencies Java, gcj, etc.
• Virtual machine host: Includes packages needed to run KVM virtual machines.
• Manually select packages: Executes apptitude allowing you to individually select packages.

Installing the package groups is accomplished using the tasksel utility. One of the important
difference between Ubuntu (or Debian) and other GNU/Linux distribution is that, when installed, a package is also configured to reasonable defaults, eventually prompting you for additional required information. Likewise, when installing a task, the packages are not only installed, but also configured to provided a fully integrated service.

Once the installation process has finished you can view a list of available tasks by entering the
following from a terminal prompt:

tasksel --list-tasks

The output will list tasks from other Ubuntu based distributions such as Kubuntu and Edubuntu. Note that you can also invoke the tasksel command by itself, which will bring up
a menu of the different tasks available.

You can view a list of which packages are installed with each task using the --task-packages option. For example, to list the packages installed with the DNS Server task enter the following:
 
tasksel --task-packages dns-server

The output of the command should list:
bind9-doc
bind9utils
bind9

Also, if you did not install one of the tasks during the installation process, but for example you decide to make your new LAMP server a DNS server as well. Simply insert the installation CD and from a terminal:

sudo tasksel install dns-server