Tuesday, May 18, 2010

Project: Getting Ready For Ubuntu 10.04 - Part 5

For our final installment, we're going to install and perform some basic configuration on our new Ubuntu 10.04 system.

Downloading The Install Image And Burning A Disk

We covered the process of getting the CD image and creating the install media in installment 3.  The process is similar.  You can download the CD image here.  Remember to verify the MD5SUM of the disk you burn.  We don't want to have a failed installation because of a bad disk.  Also, be sure to read the 10.04 release notes to avoid any last minute surprises.

Last Minute Details

There may be a few files that we will want to transfer to the new system immediately, such as the package_list.old.txt file we created in installment 4 and each user's .bashrc file.  Copy these files to a flash drive (or use Ubuntu One, if you're feeling adventuresome).


We're finally ready for the big moment.  Insert the install disk and reboot.  The install process is similar to previous Ubuntu releases.

Apply Updates

After the installation is finished and we have rebooted into our new system, the first thing we should do is apply all the available updates.  When I installed last week, there were already 65 updates.  Assuming that we have a working Internet connection, we can apply the updates with the following command:

me@linuxbox ~$ sudo apt-get update; sudo apt-get upgrade

Since the updates include a kernel update, reboot the system after the updates are applied.

Install Additional Packages

The next step is to install any additional software we want on the system.  To help with this task, we created a list in installment 4 that contained the names of all of the packages on the old system.  We can compare this list with the new system using the following script:


# compare_packages - compare lists of packages


if [[ -r $OLD_PACKAGES ]]; then
    dpkg --list | awk '$1 == "ii" {print $2}' > $NEW_PACKAGES
    diff -y $OLD_PACKAGES $NEW_PACKAGES | awk '$2 == "<" {print $1}'
    echo "compare_packages: $OLD_PACKAGES not found." >&2
    exit 1

This scripts produces a list of packages that were present on the old system but not yet on the new system.  You will probably want to capture the output of this script and store it in a file:

me@linuxbox ~ $ compare_packages > missing_packages.txt

You should review the output and apply some editorial judgement as it is likely the list will contain many packages that are no longer used on the new system in addition to the packages that you do want to install.  As you review the list, you can use the following command to get a description of a package:

apt-cache show package_name

Once you determine the final list of packages to be installed, you can install each package using the command:

sudo apt-get install package_name

or, if you are feeling especially brave, you can create a text file containing the list of desired packages to install and do them all at once:

me@linuxbox ~ $ sudo xargs apt-get install < package_list.txt

Create User Accounts

If your old system had multiple user accounts, you will want to recreate them before restoring the user home directories.  You can create accounts with this command:

sudo adduser user

This command will create the user and group accounts for the specified user and create the user's home directory.

Restore The Backup

If you created your backup using the usb_backup script from installment 4 you can use this script to restore the /usr/local and /home directories:


# usb_restore - restore directories from backup drive with rsync


sudo rsync -a $BACKUP_DIR/usr/local /usr

for h in /home/* ; do
    for d in $BACKUP_DIR$h/*; do
        if [[ -d $d ]]; then
            if [[ $d != $BACKUP_DIR$h/Examples ]]; then
                echo "Restoring $d to $h"
                sudo rsync -a "$d" $h
    for d in $ADDL_DIRS; do
        if [[ -d $d ]]; then
            echo "Restoring $d to $h"
            sudo rsync -a "$d" $h
    # Uncomment the following line if you need to correct file ownerships
    #sudo chown -R $user:$user $h

You should adjust the value of the ADDL_DIRS constant to include hidden directories you want to restore, if any, as this script does not restore any directory whose name begins with a period to prevent restoration of configuration files and directories.

Another issue you will probably encounter is the ownership of user files.  Unless the user ids of each of the users on old system match the user ids of the users on the new system, rsync will restore them with the user ids of the old system.  To overcome this, uncomment the chown line near the end of the script.

If you made your backup using the usb_backup_ntfs script, use this script to restore the /usr/local and /home directories:


# usb_restore_ntfs - restore directories from backup drive with tar


cd /
sudo tar -xvf $BACKUP_DIR/usrlocal.tar

for h in /home/* ; do
    sudo tar    -xv \
            --seek \
            --wildcards \
            --exclude="home/$user/Examples" \
            -f $BACKUP_DIR/home.tar \
            "home/$user/[[:alnum:]]*" \

To append additional directories to the list to be restored, add more lines to the tar command using the "home/$user/.ssh" line as a template.  Since tar restores user files using user names rather than user ids as rsync does, the ownership of the restored files is not a problem.


Once the home directories are restored, each user should reconfigure their desktop and applications to their personal taste.  Other than that, the system should be pretty much ready-to-go.  Both of the backup methods provide the /etc directory from the old system for reference in case it's needed.

Further Reading

Man pages for the following commands:
  • apt-cache
  • apt-get
  • adduser
  • xargs
Other installments in this series: 1 2 3 4 4a 5

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