Petter Reinholdtsen

The first wheezy based beta release of Debian Edu was wrapped up today. This is the release announcement:

New features for Debian Edu 7.1+edu0~b0 released 2013-07-27

These are the release notes for for Debian Edu / Skolelinux 7.1+edu0~b0, based on Debian with codename "Wheezy".

About Debian Edu and Skolelinux

Debian Edu, also known as Skolelinux, is a Linux distribution based on Debian providing an out-of-the box environment of a completely configured school network. Immediately after installation a school server running all services needed for a school network is set up just waiting for users and machines being added via GOsa², a comfortable Web-UI. A netbooting environment is prepared using PXE, so after initial installation of the main server from CD, DVD or USB stick all other machines can be installed via the network. The provided school server provides LDAP database and Kerberos authentication service, centralized home directories, DHCP server, web proxy and many other services. The desktop contains more than 60 educational software packages and more are available from the Debian archive, and schools can choose between KDE, Gnome, LXDE and Xfce desktop environment.

This is the fifth test release based on Debian Wheezy. Basically this is an updated and slightly improved version compared to the Squeeze release.

ALERT: Alpha based installations should reinstall or downgrade the versions of gosa and libpam-mklocaluser to the ones used in this beta release.

Software updates

• Switched roaming workstation profiles from wicd to network-manager for network configuration, as wicd didn't work any more.
• Changed version numbers of patched gosa and libpam-mklocaluser packages to make sure our locally patched versions will be replaced by the official packages when they are released from Debian. Those installing alpha version need to reinstall or manually downgrade gosa and libpam-mklocaluser.
• Added bluetooth tools to the default desktop (bluedevil, blueman).
• Added tools for sharing the desktop on KDE (krdc, krfb).
• Added valgrind to the default installation for easier debugging of crash bugs.

Other changes

• Fixed artwork package to work with gnome, no longer break desktop=gnome installations.
• Adjusted installer to now work when forced to use a proxy with the netinst CD.
• Fixed code detecting and setting/loading hardware specific setup/firmware to work more robust out of the box.
• Adjusted Kerberos setup to detect realm and server settings at install time instead of dynamically at run time. This avoid a crash with krb5-auth-dialog on diskless workstations without a DNS name.
• Worked around misfeature in network-manager not calling the dhclient exit hooks, causing automatic proxy configuration and automatic host name setting at run time to work again.
• Fixed feature setting the default Iceweasel start page from URL fetched from LDAP, to allow schools to set the global default by updating the dc=skole,dc=skolelinux,dc=no LDAP object.
• Changed default host name on all networked machines to be unique (generated from MAC or reverse DNS) after boot.
• Adjusted partition sizes to make sure they are big enough.

Known issues

• Grub is missing the new artwork.
• KDE fail to understand the wpad.dat file provided, causing it to not use the http proxy as it should.
• Chromium also fail to use the proxy.

Where to get it

To download the multiarch netinstall CD release you can use

• ftp://ftp.skolelinux.org/skolelinux-cd/wheezy/debian-edu-7.1+edu0~b0-CD.iso
• http://ftp.skolelinux.org/skolelinux-cd/wheezy/debian-edu-7.1+edu0~b0-CD.iso
• rsync -avzP ftp.skolelinux.org::skolelinux-cd/wheezy/debian-edu-7.1+edu0~b0-CD.iso .

The MD5SUM of this image is: 55d5de9765b6dccd5d9ec33cf1a07109
The SHA1SUM of this image is: 996a1d9517740e4d627d100de2d12b23dd545a3f

To download the multiarch USB stick ISO release you can use

• ftp://ftp.skolelinux.org/skolelinux-cd/wheezy/debian-edu-7.1+edu0~b0-USB.iso
• http://ftp.skolelinux.org/skolelinux-cd/wheezy/debian-edu-7.1+edu0~b0-USB.iso
• rsync -avzP ftp.skolelinux.org::skolelinux-cd/wheezy/debian-edu-7.1+edu0~b0-USB.iso .

The MD5SUM of this image is: d8f0818c51a78d357de794066f289f69
The SHA1SUM of this image is: 49185ca354e8d0543240423746924f76a6cee733

How to report bugs

http://wiki.debian.org/DebianEdu/HowTo/ReportBugs

Today I switched to my new laptop. I've previously written about the problems I had with my new Thinkpad X230, which was delivered with an 180 GB Intel SSD disk with Lenovo firmware that did not handle sustained writes. My hardware supplier have been very forthcoming in trying to find a solution, and after first trying with another identical 180 GB disks they decided to send me a 256 GB Samsung SSD disk instead to fix it once and for all. The Samsung disk survived the installation of Debian with encrypted disks (filling the disk with random data during installation killed the first two), and I thus decided to trust it with my data. I have installed it as a Debian Edu Wheezy roaming workstation hooked up with my Debian Edu Squeeze main server at home using Kerberos and LDAP, and will use it as my work station from now on.

As this is a solid state disk with no moving parts, I believe the Debian Wheezy default installation need to be tuned a bit to increase performance and increase life time of the disk. The Linux kernel and user space applications do not yet adjust automatically to such environment. To make it easier for my self, I created a draft Debian package ssd-setup to handle this tuning. The source for the ssd-setup package is available from collab-maint, and it is set up to adjust the setup of the machine by just installing the package. If there is any non-SSD disk in the machine, the package will refuse to install, as I did not try to write any logic to sort file systems in SSD and non-SSD file systems.

I consider the package a draft, as I am a bit unsure how to best set up Debian Wheezy with an SSD. It is adjusted to my use case, where I set up the machine with one large encrypted partition (in addition to /boot), put LVM on top of this and set up partitions on top of this again. See the README file in the package source for the references I used to pick the settings. At the moment these parameters are tuned:

• Set up cryptsetup to pass TRIM commands to the physical disk (adding discard to /etc/crypttab)
• Set up LVM to pass on TRIM commands to the underlying device (in this case a cryptsetup partition) by changing issue_discards from 0 to 1 in /etc/lvm/lvm.conf.
• Set relatime as a file system option for ext3 and ext4 file systems.
• Tell swap to use TRIM commands by adding 'discard' to /etc/fstab.
• Change I/O scheduler from cfq to deadline using a udev rule.
• Run fstrim on every ext3 and ext4 file system every night (from cron.daily).
• Adjust sysctl values vm.swappiness to 1 and vm.vfs_cache_pressure to 50 to reduce the kernel eagerness to swap out processes.

During installation, I cancelled the part where the installer fill the disk with random data, as this would kill the SSD performance for little gain. My goal with the encrypted file system is to ensure those stealing my laptop end up with a brick and not a working computer. I have no hope in keeping the really resourceful people from getting the data on the disk (see XKCD #538 for an explanation why). Thus I concluded that adding the discard option to crypttab is the right thing to do.

I considered using the noop I/O scheduler, as several recommended it for SSD, but others recommended deadline and a benchmark I found indicated that deadline might be better for interactive use.

I also considered using the 'discard' file system option for ext3 and ext4, but read that it would give a performance hit ever time a file is removed, and thought it best to that that slowdown once a day instead of during my work.

My package do not set up tmpfs on /var/run, /var/lock and /tmp, as this is already done by Debian Edu.

I have not yet started on the user space tuning. I expect iceweasel need some tuning, and perhaps other applications too, but have not yet had time to investigate those parts.

The package should work on Ubuntu too, but I have not yet tested it there.

As for the answer to the question in the title of this blog post, as far as I know, the only solution I know about is to replace the disk. It might be possible to flash it with Intel firmware instead of the Lenovo firmware. But I have not tried and did not want to do so without approval from Lenovo as I wanted to keep the warranty on the disk until a solution was found and they wanted the broken disks back.

A few days ago, I wrote about the problems I experienced with my new X230 and its SSD disk, which was dying during installation because it is unable to cope with sustained write. My supplier is in contact with Lenovo, and they wanted to send a replacement disk to try to fix the problem. They decided to send an identical model, so my hopes for a permanent fix was slim.

Anyway, today I got the replacement disk and tried to install Debian Edu Wheezy with encrypted disk on it. The new disk have the same firmware version as the original. This time my hope raised slightly as the installation progressed, as the original disk used to die after 4-7% of the disk was written to, while this time it kept going past 10%, 20%, 40% and even past 50%. But around 60%, the disk died again and I was back on square one. I still do not have a new laptop with a disk I can trust. I can not live with a disk that might lock up when I download a new Debian Edu / Skolelinux ISO or other large files. I look forward to hearing from my supplier with the next proposal from Lenovo.

The original disk is marked Intel SSD 520 Series 180 GB, 11S0C38722Z1ZNME35X1TR, ISN: CVCV321407HB180EGN, SA: G57560302, FW: LF1i, 29MAY2013, PBA: G39779-300, LBA 351,651,888, LI P/N: 0C38722, Pb-free 2LI, LC P/N: 16-200366, WWN: 55CD2E40002756C4, Model: SSDSC2BW180A3L 2.5" 6Gb/s SATA SSD 180G 5V 1A, ASM P/N 0C38732, FRU P/N 45N8295, P0C38732.

The replacement disk is marked Intel SSD 520 Series 180 GB, 11S0C38722Z1ZNDE34N0L0, ISN: CVCV315306RK180EGN, SA: G57560-302, FW: LF1i, 22APR2013, PBA: G39779-300, LBA 351,651,888, LI P/N: 0C38722, Pb-free 2LI, LC P/N: 16-200366, WWN: 55CD2E40000AB69E, Model: SSDSC2BW180A3L 2.5" 6Gb/s SATA SSD 180G 5V 1A, ASM P/N 0C38732, FRU P/N 45N8295, P0C38732.

The only difference is in the first number (serial number?), ISN, SA, date and WNPP values. Mentioning all the details here in case someone is able to use the information to find a way to identify the failing disk among working ones (if any such working disk actually exist).

The upcoming Saturday, 2013-07-13, we are organising a combined Debian Edu developer gathering and Debian and Ubuntu bug squashing party in Oslo. It is organised by the member assosiation NUUG and the Debian Edu / Skolelinux project together with the hack space Bitraf.

It starts 10:00 and continue until late evening. Everyone is welcome, and there is no fee to participate. There is on the other hand limited space, and only room for 30 people. Please put your name on the event wiki page if you plan to join us.

Half a year ago, I reported that I had to find a replacement for my trusty old Thinkpad X41. Unfortunately I did not have much time to spend on it, and it took a while to find a model I believe will do the job, but two days ago the replacement finally arrived. I ended up picking a Thinkpad X230 with SSD disk (NZDAJMN). I first test installed Debian Edu Wheezy as a roaming workstation, and it seemed to work flawlessly. But my second installation with encrypted disk was not as successful. More on that below.

I had a hard time trying to track down a good laptop, as my most important requirements (robust and with a good keyboard) are never listed in the feature list. But I did get good help from the search feature at Prisjakt, which allowed me to limit the list of interesting laptops based on my other requirements. A bit surprising that SSD disk are not disks according to that search interface, so I had to drop specifying the number of disks from my search parameters. I also asked around among friends to get their impression on keyboards and robustness.

So the new laptop arrived, and it is quite a lot wider than the X41. I am not quite convinced about the keyboard, as it is significantly wider than my old keyboard, and I have to stretch my hand a lot more to reach the edges. But the key response is fairly good and the individual key shape is fairly easy to handle, so I hope I will get used to it. My old X40 was starting to fail, and I really needed a new laptop now. :)

Turning off the touch pad was simple. All it took was a quick visit to the BIOS during boot it disable it.

But there is a fatal problem with the laptop. The 180 GB SSD disk lock up during load. And this happen when installing Debian Wheezy with encrypted disk, while the disk is being filled with random data. I also tested to install Ubuntu Raring, and it happen there too if I reenable the code to fill the disk with random data (it is disabled by default in Ubuntu). And the bug with is already known. It was reported to Debian as BTS report #691427 2012-10-25 (journal commit I/O error on brand-new Thinkpad T430s ext4 on lvm on SSD). It is also reported to the Linux kernel developers as Kernel bugzilla report #51861 2012-12-20 (Intel SSD 520 stops working under load (SSDSC2BW180A3L in Lenovo ThinkPad T430s)). It is also reported on the Lenovo forums, both for T430 2012-11-10 and for X230 03-20-2013. The problem do not only affect installation. The reports state that the disk lock up during use if many writes are done on the disk, so it is much no use to work around the installation problem and end up with a computer that can lock up at any moment. There is even a small C program available that will lock up the hard drive after running a few minutes by writing to a file.

I've contacted my supplier and asked how to handle this, and after contacting PCHELP Norway (request 01D1FDP) which handle support requests for Lenovo, his first suggestion was to upgrade the disk firmware. Unfortunately there is no newer firmware available from Lenovo, as my disk already have the most recent one (version LF1i). I hope to hear more from him today and hope the problem can be fixed. :)

Half a year ago, I reported that I had to find a replacement for my trusty old Thinkpad X41. Unfortunately I did not have much time to spend on it, but today the replacement finally arrived. I ended up picking a Thinkpad X230 with SSD disk (NZDAJMN). I first test installed Debian Edu Wheezy as a roaming workstation, and it worked flawlessly. As I write this, it is installing what I hope will be a more final installation, with a encrypted hard drive to ensure any dope head stealing it end up with an expencive door stop.

I had a hard time trying to track down a good laptop, as my most important requirements (robust and with a good keyboard) are never listed in the feature list. But I did get good help from the search feature at Prisjakt, which allowed me to limit the list of interesting laptops based on my other requirements. A bit surprising that SSD disk are not disks, so I had to drop number of disks from my search parameters.

I am not quite convinced about the keyboard, as it is significantly wider than my old keyboard, and I have to stretch my hand a lot more to reach the edges. But the key response is fairly good and the individual key shape is fairly easy to handle, so I hope I will get used to it. My old X40 was starting to fail, and I really needed a new laptop now. :)

I look forward to figuring out how to turn off the touch pad.

The fourth wheezy based alpha release of Debian Edu was wrapped up today. This is the release announcement:

New features for Debian Edu 7.1+edu0~alpha3 released 2013-07-03

These are the release notes for for Debian Edu / Skolelinux 7.1+edu0~alpha3, based on Debian with codename "Wheezy".

About Debian Edu and Skolelinux

Debian Edu, also known as Skolelinux, is a Linux distribution based on Debian providing an out-of-the box environment of a completely configured school network. Immediately after installation a school server running all services needed for a school network is set up just waiting for users and machines being added via GOsa², a comfortable Web-UI. A netbooting environment is prepared using PXE, so after initial installation of the main server from CD, DVD or USB stick all other machines can be installed via the network. The provided school server provides LDAP database and Kerberos authentication service, centralized home directories, DHCP server, web proxy and many other services. The desktop contains more than 60 educational software packages and more are available from the Debian archive, and schools can choose between KDE, Gnome, LXDE and Xfce desktop environment.

This is the fourth test release based on Debian Wheezy. Basically this is an updated and slightly improved version compared to the Squeeze release.

Software updates

• Dropped ispell dictionaries from our default installation.
• Dropped menu-xdg from the KDE desktop option, to drop the Debian submenu. It was not included with Gnome, LXDE or Xfce, so this brings KDE in line with the others.
• Dropped xdrawchem, xjig and xsok from our default installation as they don't have a desktop menu entry and thus won't show up in the menu now that menu-xdg was removed.
• Removed the killer system to kill left behind processes on multi-user machines, as it was no longer able to understand when a X display was in use and killed the processes of the active users too.
• Dropped the golearn (from goplay) package as the debtags in wheezy are too few to make the package useful.

Other changes

• Updated artwork matching http://wiki.debian.org/DebianArt/Themes/Joy
• Multi-arch i386/amd64 USB stick ISO available.
• Got rid of ispell/wordlist related debconf questions that showed up for some language options.
• Switched to using http.debian.net as APT source by default.
• Fixed proxy configuration on Main Server installations.
• Changed LTSP setup to ask dpkg to use force-unsafe-io the same way d-i is doing it.
• Made sure root and user passwords were not left behind in the debconf database after installation on Main Server installations.
• Made Roaming Workstation dynamic setup more robust and added draft script setup-ad-client to hook a Roaming Workstation up to a Active Directory server instead of a Debian Edu Main Server.
• Update system to install needed firmware packages during installation, to work properly in Wheezy.
• Update system to handle hardware quirks (debian-edu-hwsetup).
• Corrected PXE installation setup to properly pass selected desktop and keymap settings to PXE installation clients.
• LTSP diskless workstations use sshfs by default, allowing them to work without adding them to DNS and NIS netgroups for NFS access.

Known issues

• No mass import of user account data in GOsa (ldif or csv) available yet (698840).
• Artwork not enabled for all desktops.

Where to get it

To download the multiarch netinstall CD release you can use

• ftp://ftp.skolelinux.org/skolelinux-cd/wheezy/debian-edu-7.1+edu0~a3-CD.iso
• http://ftp.skolelinux.org/skolelinux-cd/wheezy/debian-edu-7.1+edu0~a3-CD.iso
• rsync -avzP ftp.skolelinux.org::skolelinux-cd/wheezy/debian-edu-7.1+edu0~a3-CD.iso .

The MD5SUM of this image is: 2b161a99d2a848c376d8d04e3854e30c
The SHA1SUM of this image is: 498922e9c508c0a7ee9dbe1dfe5bf830d779c3c8

To download the multiarch USB stick ISO release you can use

• ftp://ftp.skolelinux.org/skolelinux-cd/wheezy/debian-edu-7.1+edu0~a3-USB.iso
• http://ftp.skolelinux.org/skolelinux-cd/wheezy/debian-edu-7.1+edu0~a3-USB.iso
• rsync -avzP ftp.skolelinux.org::skolelinux-cd/wheezy/debian-edu-7.1+edu0~a3-USB.iso .

The MD5SUM of this image is: 25e808e403a4c15dbef1d13c37d572ac
The SHA1SUM of this image is: 15ecfc93eb6b4f453b7eb0bc04b6a279262d9721

How to report bugs

http://wiki.debian.org/DebianEdu/HowTo/ReportBugs