TechnicalOverview

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The Ubuntu developers are moving quickly to bring you the absolute latest and greatest software the Open Source Community has to offer. The Karmic Koala Alpha 1 is the first alpha release of Ubuntu 9.10, bringing with it the earliest new features for the next version of Ubuntu.

'''This is an alpha release. Do not install it on production machines. The final stable version will be released on October 29th, 2009.'''
The Ubuntu team is happy to bring you the latest and greatest software the Open Source community has to offer. This is their latest result, the Ubuntu 9.10 Release Candidate, which brings a host of exciting new features.
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To upgrade from Ubuntu 9.04 on a server system: install the {{{update-manager-core}}} package if it is not already installed; edit {{{/etc/update-manager/release-upgrades}}} and set {{{Prompt=normal}}}; launch the upgrade tool with the command {{{sudo do-release-upgrade}}}; and follow the on-screen instructions. To upgrade from Ubuntu 9.04 on a server system: install the {{{update-manager-core}}} package if it is not already installed; edit {{{/etc/update-manager/release-upgrades}}} and set {{{Prompt=normal}}}; launch the upgrade tool with the command {{{sudo do-release-upgrade -d}}}; and follow the on-screen instructions.
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= New features in Karmic =

These features are showcased for your attention. Please test them and report any bugs you find:

 http://help.ubuntu.com/community/ReportingBugs

== Updated Packages ==

As with every new release, packages--applications and software of all kinds--are being updated at a rapid pace. For a list of all packages being accepted for 9.10 Karmic Koala, please subscribe to karmic-changes:

 https://lists.ubuntu.com/mailman/listinfo/karmic-changes

== GNOME 2.26.1 (?) ==

Ubuntu 9.04 RC includes the latest [[http://library.gnome.org/misc/release-notes/2.26/|GNOME 2.26]] desktop environment with a number of great new features, including:

 * [[http://projects.gnome.org/brasero/|brasero]], version 2.26.0, developed by Philippe Rouquier and Luis Medinas, as an all-in-one CD burning application. Brasero is now the default disc burning utility in Nautilus.
{{attachment:brasero.png}}
 * Improved handling of multiple monitors with an updated {{{gnome-display-properties}}} by Federico Mena Quintero.
{{attachment:gnome-display-properties.png}}

== Linux kernel 2.6.30 ==

Alpha 1 includes the 2.6.30-4.5 [[http://kernel.org|kernel]] based on 2.6.30-rc4.

= Download Alpha 1 =
= Download =
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 http://cdimage.ubuntu.com/releases/jaunty/alpha-1/ (Ubuntu Desktop, Server, Netbook Remix, and MID) <<BR>>
 http://cdimage.ubuntu.com/edubuntu/releases/jaunty/alpha-1/ (Ubuntu Education Edition) <<BR>>
 http://cdimage.ubuntu.com/kubuntu/releases/jaunty/alpha-1/ (Kubuntu) [[https://wiki.kubuntu.org/JauntyJackalope/Alpha1/Kubuntu | Kubuntu release notes]]<<BR>>
 http://cdimage.ubuntu.com/xubuntu/releases/jaunty/alpha-1/ (Xubuntu) <<BR>>
 http://cdimage.ubuntu.com/ubuntustudio/releases/jaunty/alpha-1/ (Ubuntu``Studio) <<BR>>
 http://cdimage.ubuntu.com/mythbuntu/releases/jaunty/alpha-1/ (Mythbuntu) <<BR>>
 http://cdimage.ubuntu.com/netboot/jaunty/alpha-1/ (Ubuntu ARM)
 http://releases.ubuntu.com/releases/9.10/ (Ubuntu Desktop, Server, and Netbook Remix) <<BR>>
 http://uec-images.ubuntu.com/releases/9.10/rc (Ubuntu Server for UEC and EC2 clouds) <<BR>>
 http://releases.ubuntu.com/kubuntu/9.10/ (Kubuntu Desktop and Netbook) <<BR>>
 http://cdimage.ubuntu.com/xubuntu/releases/9.10/rc/ (Xubuntu) <<BR>>
 http://cdimage.ubuntu.com/ubuntustudio/releases/9.10/rc/ (Ubuntu``Studio) <<BR>>
 http://cdimage.ubuntu.com/mythbuntu/releases/9.10/rc/ (Mythbuntu) <<BR>>
 http://cdimage.ubuntu.com/edubuntu/releases/9.10/rc/ (Edubuntu) <<BR>>

Local mirrors are also available:

 '''FIXME: import mirror list automatically'''

= New features since Ubuntu 9.04 =

== Upstart ==
As part of our boot performance work, we have now transitioned to [[http://upstart.ubuntu.com/|Upstart]], written by Scott James Remnant. If you are testing on your primary machine, we '''strongly''' suggest having an [[http://cdimage.ubuntu.com/releases/9.10/alpha-5/|Ubuntu Karmic Alpha 5 LiveCD]] available, or creating an Alpha 5 USB startup disk before doing an upgrade. This will allow us to help you recover in the case that something goes wrong during the boot of your system after upgrade. We request that all bugs affecting the performance or functionality of boot be tagged with `ubuntu-boot` in Launchpad.

== Software Center ==
Ubuntu 9.10 RC includes the [[https://wiki.ubuntu.com/SoftwareCenter|Ubuntu Software Center]], developed by Michael Vogt, replacing 'Add/Remove' in the '''Applications''' menu.

== GNOME ==

Ubuntu 9.10 RC includes the latest [[http://live.gnome.org/TwoPointTwentyseven/|GNOME 2.28]] desktop environment with a number of great new features:

 * [[http://live.gnome.org/Empathy|Empathy]] has replaced Pidgin as the default instant messaging client, introducing the [[http://telepathy.freedesktop.org/wiki/|Telepathy framework]].

 * The gdm 2.28 login manager by William Jon Mc``Cann is a complete rewrite compared to the version in earlier Ubuntu releases, permitting a more integrated login experience.

 * Evince, the GNOME document viewer, now ships with an enforcing AppArmor profile. This greatly increases security by protecting you against flaws in the historically problematic PDF and image libraries. Users who use a non-standard location for their home directory will need to [[https://wiki.ubuntu.com/DebuggingApparmor#Adjusting%20Tunables|adjust the home tunable]] in ```/etc/apparmor.d/tunables/home```. This profile has been developed by Jamie Strandboge.

== Application development with Quickly ==

Quickly, by Rick Spencer and Didier Roche, makes it easy for developers to make new applications for Ubuntu, and to share those application with other Ubuntu users via .deb packages or personal package archives.

== Kubuntu ==

Kubuntu 9.10 includes the first Kubuntu Netbook release, Social from the Start and the latest [[http://www.kde.org|KDE]] packages. See [[KarmicKoala/RC/Kubuntu|the Kubuntu technical overview]].

== Ubuntu Enterprise Cloud Images ==

Ubuntu 9.10 RC includes images for common use on [[http://www.ubuntu.com/products/whatisubuntu/serveredition/cloud/UEC|Ubuntu Enterprise Cloud]] (UEC) and Amazon's EC2. You can try out the latest Ubuntu 9.10 server image instantly on EC2 using a preconfigured AMI, or download an image and put it into your own Ubuntu Enterprise Cloud. For information on using UEC images on Amazon EC2, see the [[https://help.ubuntu.com/community/EC2StartersGuide|EC2 Starter's Guide]].

== Ubuntu One ==

Ubuntu 9.10 RC ships with [[https://one.ubuntu.com/|Ubuntu One]] by default. Ubuntu One is your personal cloud. You can use it to back up, store, sync and share your data with other Ubuntu One users.

Ubuntu One gives all [[https://one.ubuntu.com/features/|features]] and 2 GB of essential storage to everyone. Synchronize files, contacts, and Tomboy notes across all of your Ubuntu computers and to the cloud. [[https://one.ubuntu.com/plans/|More space is available]] with a monthly subscription.

[[https://launchpad.net/ubuntuone/|Ubuntu One project information]] is available on Launchpad.

== Linux kernel 2.6.31 ==

Ubuntu 9.10 RC includes the 2.6.31-14.48 [[http://kernel.org|kernel]] based on 2.6.31.1. The kernel ships with Kernel Mode Setting enabled for Intel graphics (see below). `linux-restricted-modules` is deprecated in favour of DKMS packages.

== hal deprecation ==

Ubuntu 9.10 RC's underlying technology for power management, laptop hotkeys, and handling of storage devices and cameras maps has moved from "hal" (which is in the process of being deprecated) to "Device``Kit-power", "Device``Kit-disks" and "udev".

== New Intel video driver architecture ==

The Intel video driver has switched from the "EXA" acceleration method to the new "UXA", solving major performance problems of Ubuntu 9.04. Ubuntu 9.10 RC also features [[https://wiki.ubuntu.com/X/KernelModeSetting|kernel mode setting]] by default on Intel hardware, which reduces boot-time flickering and dramatically speeds up suspend/resume.

== ext4 by default ==

The new "ext4" filesystem is used by default for new installations with Ubuntu 9.10 RC; of course, other filesystems are still available via the manual partitioner. Existing filesystems will not be upgraded.

If you have full backups and are confident, you can upgrade an existing ext3 filesystem to ext4 by following directions in the [[http://ext4.wiki.kernel.org/index.php/Ext4_Howto#Converting_an_ext3_filesystem_to_ext4|Ext4 Howto]]. (Note that the comments on that page at the time of writing about Ubuntu's use of vol_id vs. blkid are out of date and are not applicable to Ubuntu 9.10 RC.) Maximum performance will typically only be achieved on new filesystems, not on filesystems that have been upgraded from ext3.

== GRUB 2 by default ==

GRUB 2 is the default boot loader for new installations with Ubuntu 9.10 RC, replacing the previous GRUB "Legacy" boot loader. Existing systems will not be upgraded to GRUB 2 at this time, as automatically reinstalling the boot loader is an inherently risky operation.

If you wish to upgrade your system to GRUB 2, then see the [[KernelTeam/Grub2Testing|GRUB 2 testing]] page for instructions. See also the [[http://grub.enbug.org/Manual|upstream draft manual]].

Some features are still missing relative to GRUB Legacy. Notable among these are lock/password support, an equivalent of grub-reboot, and Xen handling.

== iSCSI installation ==

The iSCSI installation process has been improved, and no longer requires `iscsi=true` as a boot parameter; the installer will offer you the option of logging into iSCSI targets if there are no local disks, or you can select "Configure iSCSI" in the manual partitioner.

Putting the root filesystem on iSCSI is now supported.

== AppArmor ==

AppArmor in Ubuntu 9.10 RC features an improved parser that uses cache files, greatly speeding up App``Armor initialisation on boot. App``Armor also now supports 'pux' which, when specified, means a process can transition to an existing profile if one exists or simply run unconfined if one does not.

Please see the [[https://help.ubuntu.com/community/AppArmor|AppArmor documentation]] for information on using App``Armor in Ubuntu.

=== New profiles ===

In addition to the above changes to App``Armor itself, several profiles were added. Enforcing profiles for ```ntpd```, ```evince```, and ```libvirt``` are enabled by default. Complain mode profiles for Dovecot are now available in the ```apparmor-profiles``` package.

A new profile is provided for Firefox as well, though it is disabled by default. Users can enable App``Armor sandboxing of their browser by running: {{{
$ sudo aa-enforce /etc/apparmor.d/usr.bin.firefox-3.5
}}}

This profile can be disabled again by performing: {{{
$ sudo apparmor_parser -R /etc/apparmor.d/usr.bin.firefox-3.5
$ sudo ln -s /etc/apparmor.d/usr.bin.firefox-3.5 /etc/apparmor.d/disable/usr.bin.firefox-3.5
}}}

An App``Armor profile is now available for Apache in the libapache2-mod-apparmor package. When used in combination with the mod_apparmor Apache module, web applications can now be protected and isolated from each other. Instructions for enabling the profile are in the /etc/apparmor.d/usr.lib.apache2.mpm-prefork.apache2 file.

Please see the [[https://wiki.ubuntu.com/SecurityTeam/KnowledgeBase/AppArmorProfiles|SecurityTeam/KnowledgeBase]] for a full listing of readily available profiles in Ubuntu.

=== Libvirt ===
Libvirt now contains App``Armor integration when using KVM or QEMU. Libvirtd is configured to launch virtual machines that are confined by uniquely restrictive App``Armor profiles. This feature significantly improves virtualisation in Ubuntu by providing user-space host protection as well as guest isolation.

== Uncomplicated Firewall ==
The [[UbuntuFirewall|Uncomplicated Firewall]] now has support for filtering by interface and egress filtering when using the ```ufw``` command. Documentation for ufw is also improved to help users better utilise the ufw framework and take full advantage of Linux netfilter's power and flexibility. See [[https://wiki.ubuntu.com/UbuntuFirewall#Features|UbuntuFirewall#Features]] for a full list of features.

== Non-eXecutable Emulation ==
[[https://wiki.ubuntu.com/Security/Features#Non-Exec%20Memory|Non-eXecutable (NX) memory protection]], also known as eXecute-Disable (XD), has always been available in Ubuntu for any systems that had the hardware to support it and ran the 64-bit kernel or the 32-bit server kernel. The 32-bit PAE desktop kernel ({{{linux-image-generic-pae}}}) now also provides the PAE mode needed for hardware with the NX CPU feature.

For systems that lack NX hardware, the 32-bit kernels now provide an approximation of the NX CPU feature via software emulation that can help block many exploits an attacker might run from stack or heap memory.

== Blocking Module Loading ==
To [[https://wiki.ubuntu.com/Security/Features#Block%20module%20loading|block the loading of any further modules]] after boot (generally for servers with unchanging hardware), the {{{/proc/sys/kernel/modules_disabled}}} one-way sysctl flag now exists to add another layer of protections against attackers loading kernel rootkits.

== Position-Independent Executables ==
Building on the work done in Ubuntu 8.10 and 9.04 to proactively protect Ubuntu from unknown threats by using [[https://wiki.ubuntu.com/CompilerFlags|strict compiler flags]], more applications have been built as [[https://wiki.ubuntu.com/Security/Features#PIE|Position-Independent Executables]] (PIE) to take advantage of the [[https://wiki.ubuntu.com/Security/Features#ASLR|Address Space Layout Randomisation]] (ASLR) available in the Ubuntu kernel.

In addition to the growing program list, PIE programs are now also built with the [[https://wiki.ubuntu.com/Security/Features#BIND_NOW|BIND_NOW]] linker flag to take full advantage of the existing [[https://wiki.ubuntu.com/Security/Features#RELRO|RELRO]] linker flag. This results in PIE programs having fewer places in their memory that can be controlled to redirect program flow when an attacker attempts memory-corruption exploits.
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As is to be expected at this stage of the release process, there are several known bugs that users are likely to run into with Karmic Alpha 1. We have documented them here for your convenience along with any known workarounds, so that you don't need to spend time reporting these bugs again: There are a small number of known bugs that users may run into with Ubuntu 9.10 RC which will be fixed before the final release. We have documented them here for your convenience along with any known workarounds.
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== Karmic Alpha 1 eats kittens if left unattended == For a full list of errata for Ubuntu 9.10, please see the [[http://www.ubuntu.com/getubuntu/releasenotes/910|Ubuntu 9.10 release notes]].
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A bug in the {{{kitten-sitter}} package in some cases leads to kittens being swallowed whole by systems running Karmic Alpha 1, nom nom. Investigation of this issue is ongoing; in the meantime it is highly recommended that you do not leave small felines unattended in the presence of Karmic Alpha 1.  * When creating LUKS encrypted partitions, some earlier versions of {{{cryptsetup}}} did not wipe out any pre-existing filesystem metadata on the partition. The current version of {{{blkid}}} used in the Ubuntu 9.10 RC will refuse to export a UUID for a partition containing more than one type of metadata signature. This means that encrypted disks may fail to be decrypted at boot time, possibly preventing the system from booting at all. Users of LUKS system-level disk encryption are advised to wait until the Ubuntu 9.10 final release before upgrading. (Bug:428435)
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= Reporting bugs =  * Empathy's MSN messaging support is provided by telepathy-butterfly, the version included in karmic advertises it supports Audio/Video chat however for stability reasons it has been disabled in Karmic. If you wish to test MSN AV support in Empathy, please install telepathy-butterfly from https://edge.launchpad.net/~telepathy/+archive/ppa and report bugs so we can make it as solid as possible in Lucid. (Bug:437828)
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It should come as no surprise that this alpha release of Karmic Koala contains other bugs. Your comments, bug reports, patches and suggestions will help fix bugs and improve future releases. Please [[http://help.ubuntu.com/community/ReportingBugs|report bugs using the tools provided]].

If you want to help out with bugs, the [[http://wiki.ubuntu.com/BugSquad|Bug Squad]] is always looking for help.
 * Installing on Marvell Dove boards requires a network connection. This will be fixed immediately after RC. (Bug:457536)
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= Help Spread the Word About Ubuntu 9.10 =

New banners are available for counting down the days until the Ubuntu 9.10 release:

  http://www.ubuntu.com/getubuntu/countdown

You can add the countdown banner to your website to help build excitement for the new release as the date approaches.

Introduction

The Ubuntu team is happy to bring you the latest and greatest software the Open Source community has to offer. This is their latest result, the Ubuntu 9.10 Release Candidate, which brings a host of exciting new features.

Upgrading from Ubuntu 9.04

To upgrade from Ubuntu 9.04 on a desktop system, press Alt+F2 and type in "update-manager -d" (without the quotes) into the command box. Update Manager should open up and tell you: New distribution release '9.10' is available. Click Upgrade and follow the on-screen instructions.

To upgrade from Ubuntu 9.04 on a server system: install the update-manager-core package if it is not already installed; edit /etc/update-manager/release-upgrades and set Prompt=normal; launch the upgrade tool with the command sudo do-release-upgrade -d; and follow the on-screen instructions.

Download

Get it while it's hot. ISOs and torrents are available at:

Local mirrors are also available:

  • FIXME: import mirror list automatically

New features since Ubuntu 9.04

Upstart

As part of our boot performance work, we have now transitioned to Upstart, written by Scott James Remnant. If you are testing on your primary machine, we strongly suggest having an Ubuntu Karmic Alpha 5 LiveCD available, or creating an Alpha 5 USB startup disk before doing an upgrade. This will allow us to help you recover in the case that something goes wrong during the boot of your system after upgrade. We request that all bugs affecting the performance or functionality of boot be tagged with ubuntu-boot in Launchpad.

Software Center

Ubuntu 9.10 RC includes the Ubuntu Software Center, developed by Michael Vogt, replacing 'Add/Remove' in the Applications menu.

GNOME

Ubuntu 9.10 RC includes the latest GNOME 2.28 desktop environment with a number of great new features:

  • Empathy has replaced Pidgin as the default instant messaging client, introducing the Telepathy framework.

  • The gdm 2.28 login manager by William Jon McCann is a complete rewrite compared to the version in earlier Ubuntu releases, permitting a more integrated login experience.

  • Evince, the GNOME document viewer, now ships with an enforcing AppArmor profile. This greatly increases security by protecting you against flaws in the historically problematic PDF and image libraries. Users who use a non-standard location for their home directory will need to adjust the home tunable in /etc/apparmor.d/tunables/home. This profile has been developed by Jamie Strandboge.

Application development with Quickly

Quickly, by Rick Spencer and Didier Roche, makes it easy for developers to make new applications for Ubuntu, and to share those application with other Ubuntu users via .deb packages or personal package archives.

Kubuntu

Kubuntu 9.10 includes the first Kubuntu Netbook release, Social from the Start and the latest KDE packages. See the Kubuntu technical overview.

Ubuntu Enterprise Cloud Images

Ubuntu 9.10 RC includes images for common use on Ubuntu Enterprise Cloud (UEC) and Amazon's EC2. You can try out the latest Ubuntu 9.10 server image instantly on EC2 using a preconfigured AMI, or download an image and put it into your own Ubuntu Enterprise Cloud. For information on using UEC images on Amazon EC2, see the EC2 Starter's Guide.

Ubuntu One

Ubuntu 9.10 RC ships with Ubuntu One by default. Ubuntu One is your personal cloud. You can use it to back up, store, sync and share your data with other Ubuntu One users.

Ubuntu One gives all features and 2 GB of essential storage to everyone. Synchronize files, contacts, and Tomboy notes across all of your Ubuntu computers and to the cloud. More space is available with a monthly subscription.

Ubuntu One project information is available on Launchpad.

Linux kernel 2.6.31

Ubuntu 9.10 RC includes the 2.6.31-14.48 kernel based on 2.6.31.1. The kernel ships with Kernel Mode Setting enabled for Intel graphics (see below). linux-restricted-modules is deprecated in favour of DKMS packages.

hal deprecation

Ubuntu 9.10 RC's underlying technology for power management, laptop hotkeys, and handling of storage devices and cameras maps has moved from "hal" (which is in the process of being deprecated) to "DeviceKit-power", "DeviceKit-disks" and "udev".

New Intel video driver architecture

The Intel video driver has switched from the "EXA" acceleration method to the new "UXA", solving major performance problems of Ubuntu 9.04. Ubuntu 9.10 RC also features kernel mode setting by default on Intel hardware, which reduces boot-time flickering and dramatically speeds up suspend/resume.

ext4 by default

The new "ext4" filesystem is used by default for new installations with Ubuntu 9.10 RC; of course, other filesystems are still available via the manual partitioner. Existing filesystems will not be upgraded.

If you have full backups and are confident, you can upgrade an existing ext3 filesystem to ext4 by following directions in the Ext4 Howto. (Note that the comments on that page at the time of writing about Ubuntu's use of vol_id vs. blkid are out of date and are not applicable to Ubuntu 9.10 RC.) Maximum performance will typically only be achieved on new filesystems, not on filesystems that have been upgraded from ext3.

GRUB 2 by default

GRUB 2 is the default boot loader for new installations with Ubuntu 9.10 RC, replacing the previous GRUB "Legacy" boot loader. Existing systems will not be upgraded to GRUB 2 at this time, as automatically reinstalling the boot loader is an inherently risky operation.

If you wish to upgrade your system to GRUB 2, then see the GRUB 2 testing page for instructions. See also the upstream draft manual.

Some features are still missing relative to GRUB Legacy. Notable among these are lock/password support, an equivalent of grub-reboot, and Xen handling.

iSCSI installation

The iSCSI installation process has been improved, and no longer requires iscsi=true as a boot parameter; the installer will offer you the option of logging into iSCSI targets if there are no local disks, or you can select "Configure iSCSI" in the manual partitioner.

Putting the root filesystem on iSCSI is now supported.

AppArmor

AppArmor in Ubuntu 9.10 RC features an improved parser that uses cache files, greatly speeding up AppArmor initialisation on boot. AppArmor also now supports 'pux' which, when specified, means a process can transition to an existing profile if one exists or simply run unconfined if one does not.

Please see the AppArmor documentation for information on using AppArmor in Ubuntu.

New profiles

In addition to the above changes to AppArmor itself, several profiles were added. Enforcing profiles for ntpd, evince, and libvirt are enabled by default. Complain mode profiles for Dovecot are now available in the apparmor-profiles package.

A new profile is provided for Firefox as well, though it is disabled by default. Users can enable AppArmor sandboxing of their browser by running:

$ sudo aa-enforce /etc/apparmor.d/usr.bin.firefox-3.5

This profile can be disabled again by performing:

$ sudo apparmor_parser -R /etc/apparmor.d/usr.bin.firefox-3.5
$ sudo ln -s /etc/apparmor.d/usr.bin.firefox-3.5 /etc/apparmor.d/disable/usr.bin.firefox-3.5

An AppArmor profile is now available for Apache in the libapache2-mod-apparmor package. When used in combination with the mod_apparmor Apache module, web applications can now be protected and isolated from each other. Instructions for enabling the profile are in the /etc/apparmor.d/usr.lib.apache2.mpm-prefork.apache2 file.

Please see the SecurityTeam/KnowledgeBase for a full listing of readily available profiles in Ubuntu.

Libvirt

Libvirt now contains AppArmor integration when using KVM or QEMU. Libvirtd is configured to launch virtual machines that are confined by uniquely restrictive AppArmor profiles. This feature significantly improves virtualisation in Ubuntu by providing user-space host protection as well as guest isolation.

Uncomplicated Firewall

The Uncomplicated Firewall now has support for filtering by interface and egress filtering when using the ufw command. Documentation for ufw is also improved to help users better utilise the ufw framework and take full advantage of Linux netfilter's power and flexibility. See UbuntuFirewall#Features for a full list of features.

Non-eXecutable Emulation

Non-eXecutable (NX) memory protection, also known as eXecute-Disable (XD), has always been available in Ubuntu for any systems that had the hardware to support it and ran the 64-bit kernel or the 32-bit server kernel. The 32-bit PAE desktop kernel (linux-image-generic-pae) now also provides the PAE mode needed for hardware with the NX CPU feature.

For systems that lack NX hardware, the 32-bit kernels now provide an approximation of the NX CPU feature via software emulation that can help block many exploits an attacker might run from stack or heap memory.

Blocking Module Loading

To block the loading of any further modules after boot (generally for servers with unchanging hardware), the /proc/sys/kernel/modules_disabled one-way sysctl flag now exists to add another layer of protections against attackers loading kernel rootkits.

Position-Independent Executables

Building on the work done in Ubuntu 8.10 and 9.04 to proactively protect Ubuntu from unknown threats by using strict compiler flags, more applications have been built as Position-Independent Executables (PIE) to take advantage of the Address Space Layout Randomisation (ASLR) available in the Ubuntu kernel.

In addition to the growing program list, PIE programs are now also built with the BIND_NOW linker flag to take full advantage of the existing RELRO linker flag. This results in PIE programs having fewer places in their memory that can be controlled to redirect program flow when an attacker attempts memory-corruption exploits.

Known issues

There are a small number of known bugs that users may run into with Ubuntu 9.10 RC which will be fixed before the final release. We have documented them here for your convenience along with any known workarounds.

For a full list of errata for Ubuntu 9.10, please see the Ubuntu 9.10 release notes.

  • When creating LUKS encrypted partitions, some earlier versions of cryptsetup did not wipe out any pre-existing filesystem metadata on the partition. The current version of blkid used in the Ubuntu 9.10 RC will refuse to export a UUID for a partition containing more than one type of metadata signature. This means that encrypted disks may fail to be decrypted at boot time, possibly preventing the system from booting at all. Users of LUKS system-level disk encryption are advised to wait until the Ubuntu 9.10 final release before upgrading. (428435)

  • Empathy's MSN messaging support is provided by telepathy-butterfly, the version included in karmic advertises it supports Audio/Video chat however for stability reasons it has been disabled in Karmic. If you wish to test MSN AV support in Empathy, please install telepathy-butterfly from https://edge.launchpad.net/~telepathy/+archive/ppa and report bugs so we can make it as solid as possible in Lucid. (437828)

  • Installing on Marvell Dove boards requires a network connection. This will be fixed immediately after RC. (457536)

Participate in Ubuntu

If you would like to help shape Ubuntu, take a look at the list of ways you can participate at

Help Spread the Word About Ubuntu 9.10

New banners are available for counting down the days until the Ubuntu 9.10 release:

You can add the countdown banner to your website to help build excitement for the new release as the date approaches.

More information

You can find out more about Ubuntu on the Ubuntu website and Ubuntu wiki.

To sign up for future Ubuntu development announcements, please subscribe to Ubuntu's development announcement list at:

KarmicKoala/TechnicalOverview (last edited 2009-10-28 16:06:36 by pD9EB68B8)