LTSP On Fedora 18 using client created on Ubuntu 12.10

Exploration of LTSP turned out to be a very interesting challenge. My motivation was to write a monthly column for Linux For You.

My primary system runs Fedora 18. I thought that I would be able to get the scripts to run on Fedora 18 in spite of the explicit caution that Fedora 15 onward is not supported. I haven't succeeded so far but I did succeed in getting an client image created on Ubuntu 12.10 to run on Fedora 18.

I installed the server scripts from the repository for experimental version of LTSP 5 for Fedora 18. This ensured that that the ldminfod version was compatible with the ldm version on Ubuntu 12.10 client.

Ubuntu uses nbd by default. Unionfs root was not working with NFS root on Ubuntu as well. So, nbd version 3.1.1 needed to be installed on Fedora. The version in Fedora repository is 2.9.20.

LTSP scripts run nbd server using xinetd while Ubuntu 12.10 runs nbd-server as a system service. Since the xinetd option did not work, nbd-server was started using a system service script. The key extract from nbd-server script is:

DAEMON="/usr/bin/nbd-server"
test -x $DAEMON || exit 0
case "$1" in
    start)
    daemon $DAEMON 10809 -C /etc/nbd-server/config

The port has to be 10809 to be compatible with the -N option used by ndb-client on Ubuntu client.

/opt/ltsp/amd64, /etc/nbd-server and  /var/lib/tftpboot/ltsp/amd64 directories was copied from Ubuntu to Fedora. The following were the final steps:

1. Run ltsp-update-sshkeys
2. Run ltsp-update-kernels
3. Run ltsp-update-image amd64 -f
4. Change the dhcpd configuration files to use the amd64 directory in tftpboot instead of i386. I modified the /etc/dhcp/dhcpd.conf file and did not use the ltsp-dhcpd script.

If all has gone well, you will get a LDM login screen with Ubuntu theme. The sessions available will be the ones on Fedora 18 and you should be able to login to a session using your Fedora 18 credentials!

Impact of OpenSUSE 12.1 on Tumbleweed

My major motivation for trying Tumbleweed was to have an Arch Linux like distribution but with delta packages. Although delta rpms were only available for the packages in the 11.4 repository and not in the Tumbleweed repository, I continued to be interested in seeing how the 'rolling' model will evolve along with the other distributions of OpenSUSE.

The release of 12.1 distribution had a larger impact on Tumbleweed than I had expected. It was literally a distribution upgrade, no different from 11.4 to 12.1. Tumbleweed repository was emptied and based on 12.1 repository. All packages were upgraded. I had hoped that the Tumbleweed distribution to be very close to the 12.1 and the upgrade should have been minimal even though I had wondered how they will manage versions across repositories.

In the current upgrade, I had to change the repository to point to the current repository instead of 11.4. The current repository is now a symbolic repository so in future no change in the repository information will be needed. However, at least at present, Tumbleweed does not really appear to be a rolling distribution. It is more like the base with some updates, so, not particularly interesting. It is better to use Ubuntu with ppa's.

I will keep watching and may be Tumbleweed will evolve into an interesting alternative. At present, I continue to stick to Fedora and Arch Linux at home and Ubuntu at work.

First Experiments with Ubuntu 11.10

The upgrade to Ubuntu 11.10 went through smoothly on Lenovo S10-3 netbook. It looks very similar to 11.04. An application would normally use the full screen as expected. I tried to start a new application and couldn't. No matter where or how hard I pushed the mouse, the dash would not appear.

Finally, I remembered the 'window' key! Having found the workaround, I have not had a chance to experiment with it more as I normally use Arch Linux on the netbook and Fedora on the desktop.

At IIT, Ropar, the default desktops are Ubuntu. So, I decided that I would try to upgrade my LTS desktop to oneiric. I certainly wasn't going to upgrade in steps. The choice was between a fresh installation or an forced update and do what is not recommended - strongly.

The latter is more fun and I hoped to learn something. I changed the sources file to use the oneiric repositories. My installation was fairly simple so I did not expect any significant issues. At worst, some packages would be broken.

Unfortunately, the upgrade failed - too many errors. The last error was a fairly simple error of some conflict in a file in two packages. I made the mistake of rebooting inspite of the broken packages!

The system no longer boots - not even grub menu :(

Well, I will now have to do a fresh installation - and haven't understood what went wrong.

Another case for Rolling distribution

While it is nice to read a news item like  "Asus will preload Ubuntu Linux on three Eee PCs", statements like the following cause a discordant note:

"The only question left is Asus' decision to ship Ubuntu 10.10 although Ubuntu 11.04 came out back in April."

In the case of open source, the users get to try the software before the vendors get around to it. Hence, rolling distributions are ideal. The vendor-supported OS will not be obsolete from the perspective advanced users and, worse, trade press, which will influence the non-tech consumers.

I wish some vendor would latch on to Arch Linux :)

Lenovo S10-3 with 2.6.36 - Resuming after Sleep

After installing the 2.6.36 kernel from Arch Linux, I found that the system would not resume after sleep. I spent the last couple of days trying to understand the problem. I installed 2.6.36 kernels from Fedora's Rawhide and from Ubuntu's kernel-ppa.

Fedora kernel had the same problem resuming. However, it worked on Ubuntu. On Ubuntu, I had been using 'intel_idle.max_cstate=0' as a kernel boot option. This was a work around for Ubuntu 10.10's boot problem on S10-3.

Removing the intel_idle option from Ubuntu's 2.6.36 kernel resulted in the S10-3 booting perfectly well. However, it showed the same inability to resume from the suspended state.

Adding that option to Arch Linux kernel resolved the resuming from sleep problem on this platform as well. Needless to say, the same option worked on Fedora kernel as well.

Rolling Distributions

It appears that Suse will have an option of a rolling distribution even if Ubuntu is not yet introducing a rolling distributions. For several years I have felt that this is inevitable (I still agree with the ideas in that article but wish I could have expressed them better).

A feature I miss in Arch Linux is the option to easily and quickly rollback the last set of updates in case some application or system malfunctions.

Unity – Great to be Different

Buying a computer – whether a pc or a notebook is really very boring. It is depressing that while we are overwhelmed by the variety of soft drinks or flavours of potato chips, there is very little choice in the marketplace in the way we interact with a computer. Of course, we can take the computer home and customise its interface to our heart's delight, but its not the same thing. It would be nice to have each vendor's computers show some distinctive character and give the salesperson a chance to talk about the differentiation. One can spend hours in the store or debating with friends as I find people doing about their smart phones. That is why I was very happy to hear the news that Ubuntu will have a non-standard interface for Gnome.
Some credit should go to Xandros for the custom interface layer they developed for EEPC701. It was just a thin layer on top of the icewm window manager but it made it very easy to use the, predominantly, KDE applications bundled with the netbook.
Developing a complete window manager is expensive but a layer to give it a unique character is well worth the branding effort.
As I implied, it does not matter whether Ubuntu's Unity interface is better. The fact that it is different makes it special. If we examine the way the major desktop managers, Gnome and KDE, are evolving, we can see that they are making it easy to support the desktops on different types of machines, including netbooks, tablets and mobile devices. In the process, they have to make it easy to create very different look and feel for a common underlying framework, widgets and applets.
KDE4.5 offers the workspace option. We can see the possibilities by comparing the desktop workspace with the netbook workspace. Soon, there will be a mobile workspace as well.
Gnome 3 is headed in the same direction. MeeGo 1.0 and Ubuntu Unity netbook 10.10 are both based on gnome. Both use the mutter window manager. It would be hard tell that by looking at them. The difference lies in a plugin for mutter and a few configuration files.
Sooner or later, some manufacturers will start to offer a custom OS. I can imagine manufacturers and desktop designers sitting and debating the character of their product, the audience they are targeting, the values they wish to promote. Introduction of the new designs can be regular events. We can have our own favourite designers. We may not have a 24x7 ftv but a couple of hours a week on the latest in UI designs seems inevitable!

Netbook Suspend and Resume

While searching for something I did not find, I came across Canonical voices page and an explanation of how suspend and resume work in Linux.

The sleep key  "is bounced back out to userspace via /proc/acpi/events (currently, though it's going to be moved to the input layer in future) and userspace gets to choose what happens next.

Let's concentrate on the common scenario, which is that someone hitting the sleep button wants to suspend to RAM. Via some abstraction (either acpid, gnome-power-manager or kpowersave or something), userspace makes that decision and initiates the suspend to RAM process by either calling a suspend script directly or bouncing via HAL." (http://www.advogato.org/article/913.html)

Hence, it is possible that a different window manager on the same hardware may behave differently. And, of course, the behaviour on different distributions can be different.

I also came across a presentation on how notebook's lid and special buttons work which gives an insight into how the hardware generates the general purpose events.

On Lenovo S10-3, the sleep key (Fn+F1) worked on each on the os's. However, the lid works perfectly well with Ubuntu, MeeGo and Smeegol but doesn't with Arch Linux even though laptop-mode tools, acpid are installed. On Ubuntu 10.10 using gdm, if I start kde, even (Fn+F1) does not work!

Thanks to the above information, I can start my hunt for why and, perhaps, a consistent solution for S10-3 no matter what the distribution or the window manager.

New Ubuntu Netbook Interface

Next step was to try the newly released 10.10 beta with a new look netbook edition. I updated the Ubuntu netbook installation. All went well, except that it would not boot with the 2.6.35 kernel used on 10.10 beta :(

Fortunately, the 2.6.32 kernel from the 10.04 version was still available and I could use that to boot and work.

The new look is indeed quite different. There is still an activity bar on top. In addition commonly used applications are available as icons in a vertical bar on the left.

Menus seems to be giving way or, at least, co-existing with search tools. A search tool is available for searching for files and applications for selecting a task to start.

There is also an applications icon in the vertical bar. It will display applications on a full screen. Grouping application in tabbed pages and a search option makes it is very nice to use.

The vertical bar of icons is quite flexible. When an application is started, the icon in the bar changes if it was already there. Otherwise the icon of the activated application is added to the bar. Both the vertical and horizontal bars are always visible. This is a trade-off between convenience of information about the system available at a glance and the desire to have as much space available for the application as possible.

Switching between applications is, thus, a single mouse click. However, it often took me time to find the icon of the application to which I wanted to switch.

I realise that the new netbook edition is a work in process. But I am inclined to favour the MeeGo or the KDE Netbook workspace approach. Hiding everything else helps one focus on the current task with minimal distraction.

Update: Booting Ubuntu 10.10 with 2.6.35-22 kernel now works by appending "intel_idle.max_cstate=0" to kernel parameter. For more details https://bugs.launchpad.net/bugs/634702

Update to Ubuntu 10.04

I downloaded the alternate iso for Ubuntu 10.04, mounted it as /media/cdrom and ran the update script.

A couple of hours later, the update was uneventfully completed while I browsed the internet and handled my emails.

I know the update is done as the theme is different and I have to move the mouse from the upper right corner to the upper left corner for closing or minimising a window.

The boot seemed to be stuck for about 10 seconds, but then the graphics display appeared. It lasted another 10 seconds and the gdm login screen appeared. I will explore the changes in the boot process of the new version of Ubuntu. However, signing in and being able to use the system took over half a minute. Overall, the time span from boot to a usable system was a little more than a minute.

And I noticed that the OpenOffice now has the Oracle logo on it.

I use Ubuntu only occasionally at home. I will explore it more at work, where I am curious whether the problems with X and old intel graphics chipset persists.

Overcoming Xserver issues on Ubuntu 9.10

Ubuntu 9.04 worked fine with 2.6.31 kernel. Switching between desktop applications was quick. This gave me the confidence of trying 9.10 again.

Xserver Freezing

Although the chipset in my system was 845 and I was not facing a blank screen on booting, I decided to use the recommendation of setting i915.modeset=0 for intel chipsets in the kernel options. Now, Ubuntu 9.10 worked well. However, the X server locked up once just before the end of the day.

Monitor Resolution Issue

For getting the monitor to work at 1280x1024 resolution, I had to add a mode line in xorg.conf file.

Progress but not yet perfect.

Getting around an Upgrade Constraint

I love to upgrade but can't compel my colleagues. So, while I use OpenOffice 3, the standard in the organisation is OO2. The documents I need to share are simple but, unfortunately, the indentation of bullets is lost when I create the document in OO3 and it is opened in OO2.

Hence, I use OO2.4 for documents I need to share with others. After installing Ubuntu 9.10, the OO2.4 installed in my personal directory would not work. Library version issue. OO2.4 needed older version of libicu libraries.

I simply copied the desired library files from the 9.04 partition and now both versions of OO work fine.

This again brings up one of the issues with current distributions. Linux allows multiple versions of libraries to exist easily. Should package managers help in keeping multiple version of some products? I believe they should. However, I also realise that it may not be easy add these capabilities into the existing distributions.

Ubuntu 9.10 - Problem with new Releases

I couldn't upgrade my Ubuntu 9.04 installation - the upgrade script wasn't on the desktop-iso I had downloaded. It wasn't critical as I had a free partition and installed Ubuntu 9.10 on that. A lucky move.

My initial reaction was very good. The 1280x1024 resolution of the monitor was not found; however, the desktop was significantly snappier on the 512 MB system. I had been expecting and looking forward to it because of the improvements in 2.6.31.

Then, I noticed that X-server would freeze occasionally. I learnt the Alt-SysRq-k combination instead of the Ctrl-Alt-Backspace. I needed to use it often. After killing the X, the screen would usually be black and I could do nothing. I had to learn the Alt-SysRq-b combination as well!

I tried to find the cause for the X locking up but could not. It may not be just the Intel driver on an old 845 graphics chipset as Google search reports problems on Nvidia and ATI chipsets as well.

By the end of the day, I had gone back to 9.04. Then I decided to copy the 2.6.31 kernel and the modules on to the 9.04 partition. I booted 9.04 with the 2.6.31 kernel from 9.10 and the system was stable for the next half hour till the end of day.

Tomorrow, I will explore that environment further and am hoping that the problem is with X. If so, I will work with the snappier 9.04 unofficial upgrade.

This confirms my view that the current mechanism for distributions is now inappropriate. It is too disruptive and, potentially, very painful.

I will find time to explore a rolling distribution Arch linux or Gentoo. My hesitation so far has been that their repositories may not be as comprehensive as Fedora or Ubuntu. Now the benefits of a rolling distribution outweigh the drawbacks.