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Revision 3 as of 2008-10-23 08:02:26

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Queste note di rilascio illustrano i problemi noti con Ubuntu 8.10 e le altre versioni.

Requisisti di sistema

The minimum memory requirement for Ubuntu 8.10 is 256 MiB of memory. (Note that some of your system's memory may be unavailable due to being used for the graphics card.)

With only the minimum amount of memory available, the installation process will take longer than normal, but will complete successfully, and the system will perform adequately once installed. Low-memory systems may be able to use the desktop CD to install by selecting "Install Ubuntu" from the boot menu to run just the installer, rather than the whole desktop started by selecting "Try Ubuntu without any change to your computer".

Pacchetti "recommended" installati in modo predefinito

In accordance with the Debian Policy Manual (which says "The 'Recommends' field should list packages that would be found together with this one in all but unusual installations"), the package management system now installs packages listed in the Recommends: field of other installed packages as well as Depends: by default. If you want to avoid this for specific packages, use apt-get --no-install-recommends; if you want to make this permanent, set APT::Install-Recommends in /etc/apt/apt.conf. Be aware that this may result in missing features in some programs.

Installazione

Avanzamento di versione

Users of Ubuntu 8.04 can upgrade to Ubuntu 8.10 by a convenient automated process. Users of older Ubuntu releases need to upgrade to Ubuntu 8.04 LTS first, and then to 8.10. Complete instructions may be found at http://www.ubuntu.com/getubuntu/upgrading.

Supporto video nVidia "legacy"

The 71 and 96 series of proprietary nVidia drivers, as provided by the nvidia-glx-legacy and nvidia-glx packages in Ubuntu 8.04, are not compatible with the X.Org included in Ubuntu 8.10. Users with the nVidia TNT, TNT2, TNT Ultra, GeForce, GeForce2, GeForce3, and GeForce4 chipsets are affected and will be transitioned on upgrade to the free nv driver instead. This driver does not support 3D acceleration.

Users of other nVidia chipsets that are supported by the 173 or 177 driver series will be transitioned to the nvidia-glx-173 or nvidia-glx-177 package instead. However, unlike drivers 96 and 71, drivers 173 and 177 are only compatible with CPUs that support SSE (e.g. Intel Pentium III, AMD Athlon XP or higher). Systems with older CPUs will also be transitioned to the nv driver on upgrade.

Device di input in X.Org

The X.Org configuration file (/etc/X11/xorg.conf) still has InputDevice entries for the mouse and keyboard, but they are ignored now because input-hotplug is used. The keyboard settings now come from /etc/default/console-setup; to change them please use sudo dpkg-reconfigure console-setup. After that, HAL and X need to be restarted (e.g., by rebooting your system).

Incompatibilità evdev xmodmap di X.Org

The X keycodes generated with the new evdev input driver in X.Org 1.5 are not compatible with those generated in Ubuntu 8.04 LTS and before. If you have configured keybindings for your user with a ~/.Xmodmap file, you will need to convert or disable it by hand on upgrade.

Applet GNOME "Termina sessione"

The "Logout" applet which appeared by default on the panel in earlier Ubuntu releases no longer offers the shutdown/reboot/hibernate/suspend actions. It is recommended that you remove this applet and replace it with the "User Switcher" applet, which now combines the previous "User switcher" and "Logout" applets. This change is not yet done automatically on upgrade (https://bugs.launchpad.net/bugs/274146)

Supporto kernel real-time per UbuntuStudio

No real-time kernel variant is available for the Linux 2.6.27 kernel included with Ubuntu 8.10. Users of UbuntuStudio 8.04 who need real-time kernel support are advised not to upgrade to UbuntuStudio 8.10.

Altri problemi noti

Timestamp TCP

Linux 2.6.27 now sets the timestamps option in TCP packets (RFC 1323), an option dating from 1992 to improve performance over high-bandwidth-times-latency paths and to improve reliability over high-bandwidth paths, which was previously omitted by mistake.

However, this change appears to cause problems for some users, believed to be due to buggy routers between the user and the destination server (for example, this has been reported by several Verizon DSL users). If your Internet connection mostly appears to be working correctly, but you have problems connecting to certain sites, then try the following command:

sudo sysctl -w net.ipv4.tcp_timestamps=0

This change will normally expire the next time you restart your computer. If it fixes the problem, then you can make the change permanent by running sudo editor /etc/sysctl.conf and adding the following line to the end of that file:

net.ipv4.tcp_timestamps = 0

The real bug here is in your router (if you own one) or your ISP's routers. If a firmware upgrade is available for your router, follow your manufacturer's instructions to upgrade it. Otherwise, contact the support department of your router manufacturer or your ISP for further advice. At the same time, Linux kernel upstream is investigating a workaround that will restore interoperability with these routers while permitting TCP timestamps to be enabled, and this fix will be evaluated for inclusion in a Stable Release Update after the 8.10 release.

See bug #264019, and thanks to Mandriva for their clear documentation of this issue.