An installation of Ubuntu 10.10 desktop on a small computer to create a desktop workstation.
This article originally used Ubuntu 10.4.1 desktop and included configuration for a network attached storage device. RAID is too difficult from the desktop edition and this article is aimed purely at desktop computers without RAID.
A spacious desktop workstation has several disks to provide storage for lots of videos or hundreds of thousands of full resolution images. The multiple disks can improve performance by allowing parallel operation. Join the disks together using RAID 1 or RAID 5 for performance combined with reliability. Some distributions of Linux make RAID easy while most desktop editions ignore RAID. This article covers RAID 1 and the standard Ubuntu desktop edition. Ubuntu has a separate alternate edition ideal for desktop computers and RAID. There are separate articles covering the alternate installation with RAID.
We are using a small quiet computer with an SSD (Solid State Disk. See Fastest processing in a small case) for the system disk and two regular disks for space.
Ubuntu is based on Debian and is more up to date. I tried this hardware with the latest Debian and Debian failed to work with the disks. Debian failed to recognise the disks with SATA set to the default AHCI mode. I switched back to the old IDE mode, Debian recognised the disks, but failed at every attempt to partition them.
Ubuntu 10.10 recognises the disks in AHCI mode.
USB CD drive
I have used an external USB DVD drive for Ubuntu installations because I have one and some of my computers do not have built in drives. Some Linux distributions are link Windows 2000 and do not like anything as modern as a USB drive. Ubuntu 10.10 installs from CD using a USB drive.
You can tell Ubuntu to wipe all the partitions on a disk then create a default configuration but Ubuntu will not always do that if there are existing partitions from Linux or Unix. At the start up menu, there is an option to Try Ubuntu without installing. You can use that option to partition your disks then save the partitions and quickly return to the installation process. I sometimes delete all the partitions then create one big one covering the whole disk then proceed for a short while then reboot and start again. This forces Ubuntu to delete the existing partition and create the default layout.
Ubuntu 10.4 and earlier provided two disk partitioning programs, Disk Utility, and Gparted. Neither actually does anything. They are just graphical user interfaces for ancient command line utilities of the type you may have used in DOS back around the 1970s. Linux copied the command line from Unix. Unix and DOS both copied the command line approach from older operating systems. DOS grew up into Windows and Unix developers decided to do the opposite of Windows. Linux suffers from the Unix legacy. Ubuntu 10.10 is finally free from the dinosaur days.
Insert the CD. Start your computer. Change the BIOS settings to boot from CD. Boot from CD. You will see a small logo of a keyboard. Touch any key on the keyboard to switch from automatic to manual. You will be asked to select your language then you see a menu.
The menu entries are:
- Try Ubuntu without installing
- Install Ubuntu
- Check disc for defects
- Test memory
- Boot from first hard disk
The first entry on the menu is the default you get if you do not switch to manual selection. The try option also creates a desktop button to jump to the second option, Install Ubuntu. The memory test is a good choice if using a new computer or resurrecting an old computer. When you first use a CD, use the Check disc option.
Check disc for defects. Ubuntu will read all the files on the disk making sure each file matches a list of sizes and content summaries. Occasionally this test highlights a download error or disk write error you might not find until the end of a long installation process. I normally test the disks on first use and mark them as tested. After the test you press any key to reboot.
The Welcome page lets you choose your language for the installation and test or install. Select your language then [Forward].
Preparing to install Ubuntu
Download updates while installing to get the latest of everything. The updates sometimes fix hardware compatibility problems. Select
Install this third-party software to get everything else that might help your computer work. 10.10 lists an MP3 improvement as an option. Select [Forward] to begin the installation.
Allocate drive space
Erase and use the entire disk then [Forward].
Ubuntu displays a proposed single partition of 60 GB on our SSD. Ubuntu actually creates two partitions with one as a swap space.
Where are you?
Ubuntu detected my location in Sydney and the current time. If Ubuntu makes the right choice for you, select [Forward] to proceed. You can also manually choose a location.
You can select a keyboard layout or choose
Figure Out Keyboard Layout to manually identify the keyboard layout. Select your keyboard then [Forward].
Who are you?
Enter your name, a name for the computer, and a password. Use a strong password because it also gives people access to your home directory even if encrypted.
Require my password to log in.
Encrypt my home folder so no one can read your information if they steal your computer. This is the reason you need a strong password.
Some of the files will install in the background while you are entering your selections. The computer will then grind away installing the rest of the files and downloading updates. The install from CD part proceeds at the speed of the CD drive plus the speed of the processor. Using a fast USB drive instead of a CD would save a few minutes in this step. The download phase is short, because it downloads only a few required and security updates, and proceeds at your network bandwidth speed. All the downloads add up to about three minutes on broadband.
The installation finishes after about 20 minutes. Select [Restart Now] to continue. A subsequent message will ask you to remove the CD then press [Enter].
At some later point you switch off the computer, remove the USB CDROM drive if you used a USB drive, then change the BIOS to not boot from CD.
The first time an application tries to write to your home directory, you will be prompted to record your encryption passphrase. Choose [Run this action now] to see your passphrase. A terminal screen appears. You type in your password at the
Passphrase: prompt. You will see a long string of letters and numbers. Write it down somewhere safe.
Ubuntu is released every 6 months. You download 670 MB as part of the release. You then apply a lot of changes to catch up. Ubuntu 10.10 was 3 months old when I started this installation and the update download was 203 MB, about 10 percent changed per month.
We selected the automatic installation of updates during the installation process but that was only hardware drivers and security updates. Select
Update Manager to push the updates through. At the end of the update you have to select [Restart Now] to finish the update.
While the updates are downloading, you can start customising Ubuntu.
Power Management to stop the screen shutting down while on mains power. Change Display to never sleep then select
Make Default. You will have to enter your password in the authentication screen. Select
Close to leave the power management screen. You can make this change while the updates are downloading.
Get rid of that distracting swirly Star Trek style background. Select
The first tab is
Theme. Change the desktop background first then return to the theme tab. Select
Background tab. Select the plain purple background at the top left then select the little purple colour icon under the pictures then select a colour of your choice in the
Pick a Color pop up page. I made the background white (#ffffff).
Theme tab. The default theme is Ambiance with lovely styling but grey on grey text in some places. Clearlooks has black on white text for easier reading on low contrast LCD screens and in sunlight. Radiance is another theme to consider for some screens.
Customise button under the themes. Select the
Colors tab in the Customise Theme page. Select the colour button in the
Background column next to
I changed the colour to #00ff33 to match the green highlights on an Acer netbook I am testing at the same time.
The background and theme change for you when logged in but not for the Ubuntu log in screen.
Netbooks and notebooks have wireless connections. I tried a few wireless cards in desktops and they rarely reach wired speeds. The metal case of desktops kills the wireless signal. You can use a USB connected wireless adaptor and place the wireless adaptor away from the metal case.
Network Connections to set up the Wireless connection if you have one. Select the
Wireless tab then
Add. Give your connection a name, usually the same as the network name or SSID.
Connect automatically for one or more wireless networks. You might set one for home and one for work.
The SSID is the id of the network. Some networks broadcast the SSID while others do not.
Select a mode of
Infrastucture for use with a router. The alternative, Ad-hoc, lets two computers talk direct without connecting through a network.
Wireless Security tab then set the security level to
WPA & WPA2 Personal. You then have to enter your password (also called a passphrase).
Available to all users then
Apply. Give the software a few seconds to connect. You can then test the connection by removing the wired network cable and browsing the Internet. Test the automatic wireless connection by restarting Ubuntu.
You can select
System Testing to test Linux on your computer. You see a long list of tests. Switch off those you do not need. You can also skip individual tests during the testing process.
Disk Utility. You should see the single 60 GB partition promised during the installation. Instead you see a 58 GB regular partition then a 2.5 GB swap partition. To make things worse by unnecessary complication, the swap partition is in an extended partition instead of a primary partition. The Linux distribution builders have some really weird ideas and, when you ask them for the logic behind their choices, they often cannot supply an answer because they are just copying what someone else did without passing on a logical reason.
Disk Usage Analyser. The Disk Usage Analyser says the total capacity of the file system in the 58 GB partition is 52.7 GB, a loss of 5.3 GB to the file system. 3.3 GB, or 6.2% of the available capacity, is used by the current installation.
You can delete and add applications using the Ubuntu Software Center. I deleted Evolution because I use Thunderbird. You can then refresh the disk usage page to see the difference. In the case of Evolution, very little changed because Evolution installs a lot of little bits and only the basic bits are deleted when you delete Evolution. You can then run the Computer Janitor to delete more unused stuff and you start to see a difference.
Test suspend and resume.
You install and delete applications by selecting
Ubuntu Software Center. You can then select programs by category or through a search.
After deleting the applications, select
Computer Janitor to clean out anything unused. The Janitor selected 90 MB of unused files to delete, files that were used for something but not any more. Collectively you can save about a gigabyte of space by deleting unused applications then cleaning up the related files.
What is the ideal partition layout if you are happy to create manual partitions? I suggest a 100 MB boot partition mounted as /boot, an 8 GB swap partition, the rest of the SSD as an Ext4 partition mounted as / then the two spare disks joined as RAID 1 with a Ext4 partition on top mounted as /home. This assumes you can create RAID partitions, something standard in the alternate download but not the desktop edition.
How do we turn our two spare regular disks into RAID? The best way is to use the Ubuntu alternate edition instead of the desktop edition as described in separate articles. There are too many painful extra steps to install RAID in the desktop edition. The rest of this page describes my attempt and the problems that make the alternate installation the preferred choice.
Ubuntu Software Center. Search for
tool to administer Linux MD arrays (software RAID) then the [Install] option. You will have to enter your password to authenticate. A screen will pop up for
Postfix configuration. Select [Forward] twice to fix Postfix. Mdadm is installed and ready for RAID.
Prepare the spare disks
Disk Utility to manage disk partitions.
On the spare disks, the ones other than your system disk, delete the existing partitions you do not want. The disks are really only useful if empty. Any other configuration is too difficult. Move all data off the target disks then delete all the partitions.
On new disks you start by formatting the disks and you get the choice of MBR or GPT (GUID Partion Table). MBR is for everything up to 2 TB. GPT is for everything over 2 TB. Your computer has a standard BIOS called a PC/BIOS. Future computers will use a BIOS called EFT. GPT is designed for EFI. Linux, the better versions of Unix, and the better versions of Windows work with GPT on EFI. Some versions of Linux and Unix work with GPT on PC/BIOS. Remember to make sure your next computer has an EFI BIOS so you can use the 3 TB disks when they arrive.
Create the RAID partition
Disk Utility, select
Create, code>RAID array to create the RAID array. You select the two disks as part of the process. After the RAID starts to build, walk away from the system for a while because large disks take a long time to format.
Create RAID Array, select
Mirror (RAID-1). The array name can be anything you want. I will use
home because I will move the home directory there. Stripe size is not used. Array size is set automatically. Select the disks you want to use, in this case 2, then select [Create].
After you select Create, you are in the disk utility with the RAID array selected. Select [Format Volume]. The format will ask you for a file type and the default Ext4 is the modern choice. Provide a partition name, often the same as the RAID array name. This is the name used in file related pages as the name for the partition.
You can take ownership of the partition and encrypt it. I will leave the partition unencrypted for simplicity and let users encrypt their home directories.
Mount volumeThe display will change to say the partition is
Mount point: Mounted at /media/home. Restart Ubuntu to test the RAID configuration. The new RAID partition should now available for your use.
At this point you find the RAID system does not start when you reboot. This problem is messy to fix and beyond the scope of this article. RAID is possible from the desktop edition but is easier from the alternative edition.
Move /home to new partition
You can use RAID for a lot of things including your home directory. You can create a new partition on additional disks then move stuff from your existing directories to new directories on your new partition. You run into paqinful trouble when you attempt to move your whole home directory somewhere else.
The ideal is to place all the home directories on RAID by moving /home to the RAID array. You can perform some of the steps using Ubuntu. You then have to perform a voodoo ritual using spells designed by old people wearing pony tails.
The next two steps are the bits you can perform without sacrificing livestock under a full moon at midnight. The third step, should you choose to persue it, might turn your computer into ashes.
Ubuntu Software Center. Search for
Grsync then the [Install] option. You will have to enter your password to authenticate.
/home as the source directory and
/media/home as the destination directory. Switch on
Preserve owner, and
Preserve group. Select the sync icon, a set of gears near the top right corner.
Change /media/home to /home
This step sounds simple but there is no application to make the change. You have to change the mount point of a partition but you cannot select it in
Places and change it. You have to enter the Linux/Unix Black Screen of Death, go back to the 1960s, and pretend your computer is running on DOS.
Do you remember DOS? No, neither can I. If you ask for help in an Ubuntu forum, some dinosaur will try to talk you through DOS commands. When you talk to them about DOS commands, they treat you like a creep from outer space because they really hate DOS. Unix uses the same commands to do the same things and Unix commands are treated like gold. Unix/DOS commands are magical when you call them Unix commands. Both can rename files and delete files. Both will fix some problems and destroy all your data with equal ease.
What Ubuntu could use is a disk administration application to perform this step. Keep yourself sane. If you want RAID for your home directory, go back to the start and install using the alternative edition of Ubuntu.
The Ubuntu desktop edition works well on computers with a small number of disks and no RAID. There are occasionally specific chip support problems with some new chips, something to look at before you buy. Ubuntu Linux is the best operating system for most computers, the desktop edition of Ubuntu is the best choice for many of the smaller desktop computers with the alternate edition the better choice when you want RAID.