Fedora Core Release Notes

You can find a tour filled with pictures and videos of this exciting new release at http://fedoraproject.org/wiki/Tours/FedoraCore6.

This release includes significant new versions of many key components and technologies. The following sections provide a brief overview of major changes from the last release of Fedora Core.

The proposed plans for the next release of Fedora are available at http://fedoraproject.org/wiki/RoadMap.

To provide feedback on Fedora software or other system elements, please refer to http://fedoraproject.org/wiki/BugsAndFeatureRequests. A list of commonly reported bugs and known issues for this release is available from http://fedoraproject.org/wiki/Bugs/FC6Common.

	Feedback for Release Notes Only
	This section concerns feedback on the release notes themselves.

If you feel these release notes could be improved in any way, you can provide your feedback directly to the beat writers. Here are several ways to do so, in order of preference:

Three new kickstart keywords have been added.

More documentation on kickstart is available in the anaconda package. To install it, run the command su -c 'yum install anaconda' and read the /usr/share/doc/anaconda*/kickstart-docs.txt file for more information.

Refer to http://fedoraproject.org/wiki/DistributionUpgrades for detailed recommended procedures for upgrading Fedora.

In general, fresh installations are recommended over upgrades, particularly for systems that include software from third-party repositories. Third-party packages remaining from a previous installation may not work as expected on an upgraded Fedora system. If you decide to perform an upgrade anyway, the following information may be helpful:

	System Configuration Backups
	Backups of configurations in /etc are also useful in reconstructing system settings after a fresh installation.

rpm -qa --last > RPMS_by_Install_Time.txt 

RPM supports parallel installation of multiple architectures of the same package. A default package listing such as rpm -qa might appear to include duplicate packages, since the architecture is not displayed. Instead, use the repoquery command, part of the yum-utils package in Fedora Extras, which displays architecture by default. To install yum-utils, run the following command:

su -c 'yum install yum-utils' 

To list all packages with their architecture using rpm, run the following command:

rpm -qa --queryformat "%{name}-%{version}-%{release}.%{arch}\n"  

You can add this to /etc/rpm/macros (for a system wide setting) or ~/.rpmmacros (for a per-user setting). It changes the default query to list the architecture:

%_query_all_fmt         %%{name}-%%{version}-%%{release}.%%{arch} 

This section covers any specific information you may need to know about Fedora Core and the PPC hardware platform.

su -c 'yum install apmud' 

boot cd: /images/netboot/ppc32.img  

This section covers any specific information you may need to know about Fedora Core and the x86 hardware platform.

This section covers any specific information you may need to know about Fedora Core and the x86_64 hardware platform.

The following packages have been split into several packages to improve performance and manageability as noted:

The php package has been split to separate the command line binary from the CGI executable.

A new version of e2fsprogs included in this release has a number of bug fixes. The ext2online feature has been integrated into resize2fs, so the ext2online program has been removed from this package.

The Fedora Project Board initiated a licensing audit to ensure all software included in Fedora Core is compliant with the package licensing guidelines. This process is now complete, and several changes were made as a result:

The process of generating kernel headers has been changed, which provides several benefits included easier maintenance and consistency.

Fedora Core may include additional patches to the kernel for improvements, bug fixes, or additional features. For this reason, the Fedora Core kernel may not be line-for-line equivalent to the so-called vanilla kernel from the kernel.org web site:

http://www.kernel.org/

To obtain a list of these patches, download the source RPM package and run the following command against it:

rpm -qpl kernel-<version>.src.rpm

To retrieve a log of changes to the package, run the following command:

rpm -q --changelog kernel-<version>

If you need a user friendly version of the changelog, refer to http://wiki.kernelnewbies.org/LinuxChanges. A short and full diff of the kernel is available from http://kernel.org/git. The Fedora version kernel is based on the Linus tree.

Customizations made for the Fedora version are available from http://cvs.fedora.redhat.com .

Fedora Core 6 includes the following kernel builds:

You may install kernel headers for all kernel flavors at the same time. The files are installed in the /usr/src/kernels/<version>-[xen|kdump]-<arch>/ tree. Use the following command:

su -c 'yum install kernel-{PAE,xen,kdump}-devel'

Select one or more of these flavors, separated by commas and no spaces, as appropriate. Enter the root password when prompted.

	Default Kernel Provides SMP
	There is no separate SMP kernel available for Fedora Core 6 on i386, x86_64 and ppc64. Multiprocessor support is provided by the native kernel.

	PowerPC Kernel Support
	There is no support for Xen or kdump for the PowerPC architecture in Fedora Core 6 test3. 32-bit PowerPC does still have a separate SMP kernel.

Refer to http://kernel.org/pub/linux/docs/lkml/reporting-bugs.html for information on reporting bugs in the Linux kernel. You may also use http://bugzilla.redhat.com for reporting bugs that are specific to Fedora.

Many of the tutorials, examples, and textbooks about Linux kernel development assume the kernel sources are installed under the /usr/src/linux/ directory. If you make a symbolic link, as shown below, you should be able to use those learning materials with the Fedora Core packages. Install the appropriate kernel sources, as shown earlier, and then run the following command:

su -c 'ln -s /usr/src/kernels/<version>.<release>-<arch> /usr/src/linux'

Enter the root password when prompted.

Fedora Core 6 does not include the kernel-source package provided by older versions since only the kernel-devel package is required now to build external modules. Configured sources are available, as described in this kernel flavors section.

	Instructions Refer to Current Kernel
	To simplify the following directions, we have assumed that you want to configure the kernel sources to match your currently-running kernel. In the steps below, the expression <version> refers to the kernel version shown by the command: uname -r.

Users who require access to Fedora Core original kernel sources can find them in the kernel .src.rpm package. To create an exploded source tree from this file, perform the following steps:

	Do Not Build Packages as Super-user (root)
	Building packages as the superuser is inherently dangerous and is not required, even for the kernel. These instructions allow you to install the kernel source as a normal user. Many general information sites refer to /usr/src/linux in their kernel instructions. If you use these instructions, simply substitute ~/rpmbuild/BUILD/kernel-<version>/linux-<version>.<arch>."]]

	Building Kernel Binary RPMs
	Normally, kernels for Fedora are built using the rpmbuild utility and a specfile. Your results may vary if you use the kernel's built-in make rpm target.

An exploded source tree is not required to build a kernel module, such as your own device driver, against the currently in-use kernel. Only the kernel-devel package is required to build external modules. If you did not select it during installation, use Pirut to install it, going to Applications → Add/Remove Software or use yum to install it. Run the following command to install the kernel-devel package using yum.

su -c 'yum install kernel-devel' 

For example, to build the foo.ko module, create the following Makefile in the directory containing the foo.c file:

obj-m := foo.o 

KDIR  := /lib/modules/$(shell uname -r)/build
PWD   := $(shell pwd)

default:
    $(MAKE) -C $(KDIR) M=$(PWD) modules

Issue the make command to build the foo.ko module.

AIGLX, from the Fedora Rendering Project, is part of the upstream X.org 7.1 release included in Fedora Core 6. X.org compositing is enabled by default in this release. Compositing features in Metacity, the default window manager provided in GNOME, are disabled in this release. When desktop effects are enabled, Metacity is replaced by Compiz, an OpenGL compositing window manager that uses AIGLX to provide desktop effects.

To enable the fancy desktop effects, follow these steps:

If you get stuck, refer to the following thread:

A list of hardware that supports these effects is available at http://fedoraproject.org/wiki/RenderingProject/aiglx.

The performance for the yum software management utility has been greatly improved in Fedora Core 6. The repository metadata parser has now been implemented in C. A new mirror management infrastructure also ensures better mirror selection and, in most cases, faster performance. The Pirut package management tool and the Pup software update utility are based on yum, so their performance is likewise improved.

This release features GNOME 2.16. Many of the changes in GNOME 2.16, such as Tomboy and the GNOME Power Manager, were added in Fedora Core 5. Fedora Core 6 also features the Orca screen reader, and the Alacarte menu editor previously available from Fedora Extras.

The GNOME Power Manager utility now provides detailed, graphical information about power consumption. To access this information, right click on the applet and select the Information menu item.

The GNOME splash screen has been disabled upstream intentionally. To enable it, use gconf-editor or the following command:

gconftool-2 --set /apps/gnome-session/options/show_splash_screen --type bool true 

The lock screen dialog theme is not connected to the selected screensaver in this release. To enable it, use gconf-editor or the following command:

gconftool-2 --set  --type string /apps/gnome-screensaver/lock_dialog_theme  "system"  

There is no longer a browser suite package contained in Fedora Core 6. The mozilla package has been removed. For equivalent functionality, use firefox as a web browser and thunderbird as a mail client, or use seamonkey, a browser suite distributed in Fedora Extras.

To better support certain scripts (such as Indic and some CJK scripts), Fedora builds its Firefox using the Pango system as its text renderer. Pango is used with the permission of the Mozilla Corporation. This change may negatively impact performance on some pages. To disable the use of Pango, set MOZ_DISABLE_PANGO=1 in your environment before launching Firefox.

export MOZ_DISABLE_PANGO=1
/usr/bin/firefox

Gecko based browsers Firefox and Epiphany now properly render MathML when using the Pango text backend. Additionally, several issues with the rendering and behavior of text when using the Pango text backend have been resolved. Epiphany now renders using Pango by default.

Thunderbird in Fedora now enables Pango by default for all locales with permission from the Mozilla Corporation. This change may negatively impact performance on some pages. To disable the use of Pango, set MOZ_DISABLE_PANGO=1 in your environment before launching Thunderbird.

export MOZ_DISABLE_PANGO=1
/usr/bin/thunderbird

These are the new features in glibc:

The linker includes support for the new ELF symbol hash table format. Use the --hash-style option of the linker to select the format(s).

12.2.1. Kernel header files

This release of Fedora has been built using Linux kernel headers exported directly from the kernel, using the new headers_install feature of the 2.6.18 kernel. Thus, the glibc-kernheaders package has been removed and replaced with kernel-headers, a subpackage of kernel.

Developers may notice some changes between these new kernel headers and what was present before, including but not limited to the following:

• The <linux/compiler.h> header file has been removed, since it contains nothing of use to userspace.

• The _syscallX() macros are removed. Userspace should use syscall() from the C library instead.

• The PAGE_SIZE macro is removed from some architectures, since the page size is variable. Userspace should be using sysconf(_SC_PAGE_SIZE) or getpagesize() instead.

• The <asm/atomic.h> and <asm/bitops.h> header files have been removed. These were not designed for use in userspace, and would fail to compile on some architectures while silently giving non-atomic behaviour on others. The C compiler provides its own atomic builtin functions that are suitable for use in userspace programs instead.

• Content that was previously protected with #ifdef __KERNEL__ is now elided completely with the unifdef tool. Defining __KERNEL___ in order to see parts that should not be visible to userspace is no longer effective.

In addition, some other header files that xare not suitable for use in userspace have been removed, and still more headers have been edited to remove unsuitable content.

	Kernel header changes are not Fedora-specific
	These changes are inherited from the upstream kernel and are not specific to Fedora. Any distribution using the current officially-exported kernel headers would be the same.

The standard search path for Ruby libraries, $:, has changed in accordance with the packaging guidelines. Changes were also made to some of the entries in Config::CONFIG in the rbconfig module. The most important changes include:

Directories that were previously in $: remain there for the time being, so that existing code, such as /usr/lib/site_ruby, does not need to be modified. These directories are deprecated though, and will be removed by the release of Fedora Core 8. Build Ruby RPM packages in accordance with the packaging guidelines. In particular, Ruby libraries should only be installed into sitelibdir and sitearchdir. You should also follow this rule for Ruby code that is not packaged as an RPM.

A general introduction to the many proactive security features in Fedora, the current status, and policies is available at http://fedoraproject.org/wiki/Security.

This release increases usability of SELinux by providing a graphical troubleshooting tool, setroubleshoot. SELinux developer Dan Walsh explains the tool and its usage in his blog. The Nautilus file manager has also been improved in GNOME 2.16 to display SELinux contexts.

The SELinux project pages have troubleshooting tips, explanations, and pointers to documentation and references. Some useful links include the following:

In addition to the java-gcj-compat free software stack, Fedora Core lets you install multiple Java implementations and switch between them using the alternatives command line tool. However, every Java system you install must be packaged using the JPackage Project packaging guidelines to take advantage of alternatives. Once these packages are installed properly, the root user may switch between java and javac implementations using the alternatives command:

alternatives --config java  
alternatives --config javac

The 64-bit JNI libraries shipped by default on x86_64 systems in Fedora Core and Extras do not run on 32-bit JREs. Either switch to a 64-bit Java alternative, or install the 32-bit version of the packages, if available. To install a 32-bit version, use the following command:

yum install <package_name>.i386 

Likewise, the 32-bit JNI libraries shipped by default on ppc64 systems do not run with a 64-bit JRE. To install the 64-bit version, use the following command:

yum install <package_name>.ppc64 

This release of Fedora Core includes a preview release of gcjwebplugin, a Firefox plugin for Java applets. gcjwebplugin is not enabled by default. Although the security implementation in GNU Classpath is being actively developed, it is not mature enough to run untrusted applets safely. That said, the AWT and Swing implementations in GNU Classpath are now sufficiently mature that they can run many applets deployed on the web. Adventurous users who want to try gcjwebplugin can read /usr/share/doc/libgcj-4.1.1/README.libgcjwebplugin.so, as installed by the gcc rpm. The README explains how to enable the plugin and the risks associated with doing so.

Fedora Core includes many packages derived from the JPackage Project, which provides a Java software repository. These packages are modified in Fedora to remove proprietary software dependencies and to make use of GCJ's ahead-of-time compilation feature. Use the Fedora repositories to update these packages, or use the JPackage repository for packages not provided by Fedora. Refer to the JPackage website at http://jpackage.org for more information on the project and the software it provides.

	Mixing Packages from Fedora and JPackage
	Research package compatibility before you install software from both the Fedora and JPackage repositories on the same system. Incompatible packages may cause complex issues.

This release of Fedora Core includes Fedora Eclipse, which is based on the Eclipse SDK version 3.2. The "New and Noteworthy" page for this release can be accessed here.

Released in June 2006, the SDK is known variously as "the Eclipse Platform," "the Eclipse IDE," and "Eclipse." The Eclipse SDK is the foundation for the combined release of ten Eclipse projects under the Callisto combined release umbrella. A few of these Callisto projects are included in Fedora Core and Extras: CDT, for C/C++ development, and GEF, the Graphical Editing Framework.

We hope to augment these projects with others as this Fedora cycle goes on. Likely candidates for inclusion include EMF, the Eclipse Modeling Framework, and VE, the Visual Editor. As of this writing, it is expected that an updated version of PyDev, the Python development tools, is going to be available in Fedora Extras. Assistance in getting these projects packaged and tested with GCJ is always welcome. Contact the interested parties through fedora-devel-java-list and/or #fedora-java on freenode.

Fedora also includes plugins and features that are particularly useful to FOSS hackers: ChangeLog editing with eclipse-changelog and Bugzilla interaction with eclipse-bugzilla. Our CDT package also includes work-in-progress support for the GNU Autotools. The latest information regarding these projects can be found at the Fedora Eclipse Project page.

The default installation of Fedora Core includes Rhythmbox and Totem for media playback. The Fedora Core and Fedora Extras repositories include many other popular programs such as the XMMS player and KDE's amaroK. Both GNOME and KDE have a selection of players that can be used with a variety of formats. Third parties may offer additional programs to handle other formats.

Fedora Core also takes full advantage of the Advanced Linux Sound Architecture (ALSA) sound system. Many programs can play sound simultaneously, which was once difficult on Linux systems. When all multimedia software is configured to use ALSA for sound support, this limitation disappears. For more information about ALSA, visit the project website at http://www.alsa-project.org/. Users may still experience issues when multiple users log into the system. Depending upon hardware and software configurations, multiple users may not be able to use the sound hardware simultaneously.

Helix Player has been removed from this release since it duplicates the functionality of Totem. Totem also uses the GStreamer media framework, which is used by other multimedia applications in Fedora Core. With GStreamer, users can easily add support for additional codecs to all included applications.

Fedora includes complete support for the Ogg media container format and the Vorbis audio, Theora video, Speex audio, and FLAC lossless audio formats. These freely-distributable formats are not encumbered by patent or license restrictions. They provide flexible alternatives to more popular, restricted formats. The Fedora Project encourages the use of open formats in place of restricted ones. For more information on these formats and how to use them, refer to the Xiph.Org Foundation's web site at http://www.xiph.org/.

Fedora Core and Fedora Extras software repositories cannot include support for MP3 or DVD video playback or recording. The MP3 formats are patented, and the patent holders have not provided the necessary patent licenses. DVD video formats are patented and equipped with an encryption scheme. The patent holders have not provided the necessary patent licenses, and the code needed to decrypt CSS-encrypted discs may violate the Digital Millennium Copyright Act, a copyright law of the United States. Fedora also excludes other multimedia software due to patent, copyright or license restrictions, including Adobe's Flash Player and and Real Media's Real Player. For more on this subject, please refer to http://fedoraproject.org/wiki/ForbiddenItems.

While other MP3 options may be available for Fedora, Fluendo now offers a free MP3 plugin for GStreamer that has the necessary patent license for end users. This plugin enables MP3 support in applications that use the GStreamer framework as a backend. Fedora does not include this plugin since we prefer to support and encourage the use of patent unrestricted open formats instead. For more information about the MP3 plugin, visit Fluendo's website at http://www.fluendo.com/.

Fedora Core and Fedora Extras software repositories includes a variety of tools for easily mastering and burning CDs and DVDs. GNOME users can burn directly from the Nautilus file manager, or choose the gnomebaker or graveman packages from Fedora Extras, or the older xcdroast package from Fedora Core. KDE users can use the robust k3b package, available in Fedora Extras, for these tasks. Console tools include cdrecord, readcd, mkisofs, and other popular applications.

You can use Fedora to create and play back screencasts, which are recorded desktop sessions, using open technologies. Fedora Extras software repository includes istanbul, which creates screencasts using the Theora video format. These videos can be played back using one of several players included in Fedora Core. This is the preferred way to submit screencasts to the Fedora Project for either developer or end-user use. For a more comprehensive how-to, refer to http://fedoraproject.org/wiki/ScreenCasting.

Most of the media players in Fedora Core and Fedora Extras software repositories can use plugins to add support for additional media formats and sound output systems. Some use powerful multimedia frameworks, such as the gstreamer package, to handle media format support and sound output. Fedora Core and Fedora Extras software repositories offer plugin packages for these backends and for individual applications. Third parties may provide additional plugins to add even greater capabilities.

Under Fedora Core 6 using Xen 3.0.2, both paravirtualization and full virtualization can be implemented. Full virtualization requires a VT-capable processor. Paravirtualization does not require special hardware, but does require the guest OS to be modified. To learn more about how to configure and use Xen, refer to http://fedoraproject.org/wiki/FedoraXenQuickstartFC6.

The Fedora Core 6 development team has tested Xen with Fedora Core 6 and Red Hat Enterprise Linux 5 Beta1 guests. Other guests have not been tested. With paravirtualization, however, users can expect reasonable success running any Linux guest OS that was built for Xen 3.0.2. With full virtualization using VT hardware, users can expect reasonable success with a larger variety of operating systems, including some proprietary operating systems.

In Fedora Core 6 a single kernel supports both the host and the guest operating systems. In previous versions, there was one kernel, kernel-xenU, for the host or hypervisor and a separate kernel, kernel-xen0, for the guests. In Fedora Core 6 the kernel-xen package is the only kernel needed.

Fedora Core 6 introduces virt-manager, a GUI application for installing and managing virtual machines. Features of virt-manager include: