Fedora 9 Week: Package Management from the Command Line

nospam@example.com (Chris Tyler) — Tue, 27 May 2008 00:01:00 -0400

This article is part of Fedora 9 Week.

In Fedora 9, the default package manager has changed from Yum to PackageKit. PackageKit is a system service that can queue package installation and removal requests. In Fedora 9 it works with a Yum-based backend (and can work with other backends on other systems).

To manage packages from the command line in Fedora 9, there are two options available: first, you could continue to use the yum command which is still present. The second option is to use the PackageKit command-line tool, pkcon, which works a lot like the yum command but which interfaces with the PackageKit service.

Like yum, pkcon accepts a subcommand and arguments. Here are some of the more common uses and the closest corresponding yum command:

pkcon command	yum command	description
pkcon search name pattern	yum list pattern	lists packages with names containing pattern (note: with yum it's necessary to specify wildcard astrisks if required.).
pkcon search details pattern	yum search pattern	lists packages with details (including description) containing pattern
pkcon install packageId	yum install packagename	installs the designated package
pkcon install-file filename	yum localinstall filename	installs the designated RPM file, resolving dependencies through yum repositories as required
pkcon update-system	yum update	update all packages on the system for which updates are available
pkcon update packageId	yum update packagename	update only the specified package
pkcon get description packageId	yum info packagename	get detailed information on the specified package
pkcon get depends packageId	yum deplist packagename	display dependency information for a package

Since pkcon queues requests with the PackageManager service, it does not ask for confirmation before proceeding with an installation or removal (which is the default behavior for yum). However, you do have the option of adding the -n option to the command line to enqueue a request without waiting for it to complete.

Fedora 9 Week: Installing Over an Existing System with LVM

nospam@example.com (Chris Tyler) — Mon, 26 May 2008 00:02:00 -0400

This article is part of Fedora 9 Week.

When installing Fedora 9 onto a system which already has a Fedora installation, it can be hard to decide whether to do an upgrade or a full reinstallation. Doing an update preserves virtually all of you data and settings, but doing a reinstallation gives a completely clean slate (at the expense of your data -- even if you use a separate /home filesystem, there are often system settings, web sites, and other data in /etc and /var).

Fortunately, when using logical volume management (the default storage scheme in Fedora), you can choose a middle ground: install the new version of Fedora onto a different logical volume without disturbing the existing LVs. The technique is simple:

1. Ensure that there is some space within your volume group which is not allocated to a logical volume. The easiest way to do this is by booting from the Fedora Live Disc image, and then using system-config-lvm.

2. Start the normal Fedora installer (from the install DVD) and select Instllation (not upgrade). When you reach the partitioning screen, select Create Custom Layout.

3. On the custom layout screen, double-click on your main volume group (named VolGroup00 if you used the default VG naming scheme during the previous Fedora instllation).

4. Select each of our previous filesystems and create a custom mountpoint for each (for example, if you had just one LV filesystem -- the root one, from Fedora 8 -- you may want to mount it as /f8root). Do not format these filesystems. If you have filesystems such as a home that you wish to use, specify the appropriate mountpoint for each (e.g., /home).

5. Create a new logical volume to hold the new root filesystem. Give it a descriptive name such as "f9root" and specify / as the mountpoint. 10 GB is a reasonable minimum size for this filesystem (you can go as small as 4 GB). If you don't already have a /home filesystem, consider creating one in a logical volume to make upgrading easier next time.

6. Click Ok in the Edit LVM Volume Group window to close it. Double-click on your old /boot partition and specify /boot as the mountpoint (consider formatting this partition).

7. Proceed with the installation as usual.

One the system has been fully installed, you can simply copy any needed file from your old system (/f8root) to your new system (/). Once you're certain that you don't need the old filesystem any more, you can remove it (and again, system-config-lvm provides a simple way to do this graphically).

Fedora Daily Package - Fedora 9 Week

Fedora 9 Week: Package Management from the Command Line

Fedora 9 Week: Installing Over an Existing System with LVM