Fedora Daily Package

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.

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).

Start your download... we'll switch the Fedora Daily Package over to F9 starting next Monday with a Focus Week. Update: Let's make that the 26th ... it's been a little busy around here!

If you're in the Greater Toronto Area, we'd love to have you at the Fedora 9 Release Party at LinuxCaffe tonight (don't forget a blank disc or USB key!). Andrew Overhold has posted the full details.

The Fedora community includes artists of all stripes, including (I'm told, but haven't yet heard) some great musicians. It figures that Fedora would have some good music tools.

Hydrogen is an advanced drum machine. It has a Qt-based MDI-style interface, with mixer, song editor, pattern editor, drumkit manager, and instrument editor subwindows. Included drumkits (sample sets) include GeneralMIDI (emulating a Roland XV-5080) and Roland TR-808. Although I'm not a musician, the interface is straightforward enough that I was able to begin experimenting quickly, starting with the included demo files.

So whether your garage band drummer is on vacation, you've always wanted to express your rhythmic side (or you've just got to have have More Cowbell!), or you're looking for a serious drum machine, Hydrogen is worth a look.

Note: On my F8 system, I was unable to get Hydrogen to work with PulseAudio and had to stop the pulseaudio daemon (killall pulseaudio) before starting Hydrogen.

Installing from the command line: yum install hydrogen
Installing using the graphical installer: Not available in the Browse view; use the Search or List view to install hydrogen
Menu location after installation: Applications > Sound & Video > Hydrogen Drum Machine
Command: /usr/bin/hydrogen
Upstream website: http://www.hydrogen-music.org/

The top command shows which processes are currently taking the most CPU time and memory, and iotop displays current input/output usage. iftop is a little-known cousin which displays network usage by connection. The default display shows the connection endpoints (port numbers may be toggled using the p key), with data transfer volumes displayed in numeric format and as a horizontal bargraph using reverse video. Various keys provide control over the display; pressing ? displays a help page listing these keys. iftop also provide command-line options for traffic filtering and interface selection.

The information displayed by iftop is detailed and easily understood. When an application is hogging your network bandwidth, iftop can be an invaluable tool -- though you may need to also use netstat -p to determine which process is behind a particular connection.

Thanks to John Poelstra for suggesting iftop.

Installing from the command line: yum install iftop
Installing using the graphical installer: Not available in the Browse view; use the Search or List view to install iftop
Menu location after installation: Not on the menu; run the command /usr/sbin/iftop in a terminal as root
Command: /usr/sbin/iftop
Upstream website: http://www.ex-parrot.com/~pdw/iftop/

The Battle for Wesnoth is a well-developed turn-based strategy battle game. It offers single-player, multi-player, and network modes and has a easy-to-use and engaging hextile user interface. It's a lot of fun to play -- but easily addictive.

What I find most impressive about this game is the size and activity of its community, which has developed extensive documentation, a built-in tutorial, nice artwork, a large number of maps, and a great soundtrack, and maintains very active forums and game servers. Open source at its best!

Note: The main package, wesnoth, appears in the Browse view of the Fedora 8 Pacakge Manager (Pirut), but don't miss the optional wesnoth-server and wesnoth-tools packages which do not appear in the Browse view -- these packages provide a network server and a game editor.

Thanks to Gayathri Swaminathan for suggesting this package!

Installing from the command line: yum install wesnoth
Installing using the graphical installer: Applications > Games and Entertainment > wesnoth
Menu location after installation: Applications > Games > Battle for Wesnoth
Command: /usr/bin/wesnoth
Upstream website: http://www.wesnoth.org/

The Linux filesystem permission model comes from Unix. It provides three permissions (read, write, and execute) for three communities (the user that owns the file, users in the group that owns the file, and all other users). The beauty of this model is its simplicity: it's easy to understand and compact to display. By creating various groups of users, this scheme can accommodate most use cases.

But sometimes the traditional model just isn't convenient, and having many different groups becomes a real pain to manage. Filesystem access control lists (ACLs) mend this pain by extending the traditional model to permit individual permissions to be set for any number of users and groups.

The setfacl and getfacl commands are used to manage ACLs from the command line, and ls -l will display a plus-sign beside the permission of any file which has an extended access control list:

$ ls -l ~/Desktop/lux-handout
-rw-rw-r--+ 1 chris chris 821 2008-05-03 15:21 /home/chris/Desktop/lux-handout

The Eiciel package provides a graphical user interface for managing ACLs. Although this package provides a stand-alone application, it really shines as a Nautilus extension -- if you're using Gnome, simply right-click on a file and select Properties, and you'll see an Access Control List tab with the Eiciel display.

Note: ACLs are only available on filesystem that support extended attributes. Fortunately, this includes ext2/ext3/ext4 (the default filesystems in Fedora), JFS, and ReiserFS. However, FAT, NTFS, NFS, and CIFS (Samba) do not support ACLs at this time.

Bug: The Eiciel display includes a checkbox labeled "Also show system participants". You will need to check this box to see users with a user ID below 1000. This control is intended to hide system accounts such as root and mysql, but on a Fedora system, regular user IDs start at 500, not 1000. See bug 445667 for details.

Installing from the command line: yum install eiciel
Installing using the graphical installer: Base System > System Tools > eiciel
Menu location after installation: Applications > System Tools > Eiciel or right-click on a file within Nautilus, select Properties, go to the Access Control List tab
Command: /usr/bin/eiciel
Upstream website: http://rofi.roger-ferrer.org/eiciel/

Fedora 9 is only a few days away, as the counter on the front page testifies. Although it's possible to upgrade an earlier Fedora system to F9, it's generally agreed that a fresh installation is cleaner and has less potential for problems. If your system uses LVM (which has been the default for the last several Fedora releases), it's particularly easy to perform a fresh installation while maintaining access to your previous data, because you can create new Logical Volumes within your existing Volume Group. You can then mount your old filesystems and migrate data over with ease.

This type of installation will be covered in the upcoming F9 Focus Week, but in order to prepare for it, you'll need some free space within your volume group -- I'd recommend at least 6-10 GB. If you're not really comfortable with the LVM commands, you can explore and adjust your LVM configuration using the system-config-lvm tool; however, to reduce the size of a logical volume and free up some space, the filesystem within that logical volume must be unmounted -- and in the case of the root filesystem, that means that the system can't be running in its normal way, which pretty much precludes the use of system-config-lvm. To reduce the size of the root filesystem, see the article on Using LVM In Rescue Mode from System Recovery Week.

(Note the links above -- sorry if they're not very visible or obvious due to the styling).

Update: KageSenshi points out that system-config-lvm is on the Fedora live disc images. You can resize the root filesystem on the hard disk by simply booting from a live disc and running the system-config-lvm command from a terminal window.