New KVM Option

The Edimax KVM will hopefully be on its way back to Amazon on Monday.

Extracting all the leads that I had pre-routed through the trunking behind my new built-in desk was a lot harder than I expected. This was largely because I’d run the wires through the trunking, and then attached the trunking to the wall/desk. Getting them back out without removing the trunking from the wall was not trivial. About an hour into the process I was really starting to regret (a lot) that I’d not tested the KVM before running all the cables. Needless to say, I won’t make that mistake again.

Speaking of which, the new KVM is now on it’s way.

This time I did a LOT more checking of the specifications and reviews before making my selection. Fundamentally my basic needs hadn’t changed, but this time I was a lot more aware of the subtle differences in the manufacturers descriptions of the units. It’s very clear that at the cheaper end of the market most of the manufacturers take one of a couple of old reference designs, and repackage & rebadge them. These wouldn’t support my needs. The key additional criteria I looked for this time was mention of support for laptops, and specifically support for Windows 7.

Windows 7 support is essential because it indicates a KVM that has full support for EDID emulation, which (I believe) is probably also a requirement for the newer Linux desktop environments such as Unity and Gnome Shell. I’m now pretty sure that this is where the Edimax fell short.

In the end, the two cheapest devices that did everything I needed seem to be the ATEN CS64U, and the IOGEAR GCS1804. The IOGEAR is the fuller featured device, with detachable leads etc, but it’s difficult to source in the UK, and comes with a £140 price point. Whereas the ATEN is a bit more restricted (no OSD for example), but is available from Amazon for only £40.

That made the decision trivial.

The search for a new desktop still continues

Back in my last post I described how I attempted to customise the Unity desktop environment to better suit my needs within my admittedly commercial setting. The results weren’t too bad, but exposed a series of issues, some of which were purely personal and subjective, and some I felt to be genuine bugs, which I raised against the Unity interface.

This post is all about the same attempt, but this time with the Gnome 3 Shell.

So, having freshly installed Ubuntu 11.10, we need to install Gnome Shell. It’s in the repositories, so it’s a simple matter of opening a terminal and issuing the command:
sudo apt-get install gnome-shell

The steps I then followed were:

1. Getting to a shell prompt with Alt + F2 has been disabled by default in Gnome Shell under Ubuntu 11.10. This is annoying, as it means you can’t (trivially) restart or debug the desktop environment without it. To fix it, open “System Settings” and under the Keyboard settings, go to Shortcuts, then System, and then click the “Disabled” next to “Show the run command prompt” and press Alt + F2 to re-enable the command prompt.
2. Next I added some Gnome Shell customisations from http://extensions.gnome.org, which make Gnome Shell look a lot more like Gnome 2. Heretical? Perhaps. So shoot me.
   1. Frippery Applications Menu – puts an old-school applications menu on the left side of the top menu
   2. Frippery Bottom Panel – adds a taskbar to the bottom of every workspace
   3. Frippery Move Clock – moves the clock back to where it used to be in Gnome 2.xx
   4. Frippery Panel Favorite – adds a copy of the launcher into the top panel
3. Next, I wanted to remove the accessibility icon from the top panel. Last time I looked, I didn’t need any of those settings, so I certainly don’t need the icon there all the time. To get rid of it, I downloaded an extension from the website of the author of all the previous extensions:
   http://www.fpmurphy.com/gnome-shell-extensions/noa11y-2.0.tar.gz

   This needs to be unpacked into ~/.local/share/gnome-shell/extensions/ by cd’ing to that directory and running something like:
   tar xvf ~/Downloads/noa11y-2.0.tar.gz.

   You then need to install Gnome Tweak to be able to enable the extension:
   sudo apt-get install gnome-tweak-tool
   and then run it with gnome-tweak-tool and choose to enable or disable whatever extensions you have loaded.

4. As with Unity, I wanted to disable the overlay scrollbars:
   sudo su
echo "export LIBOVERLAY_SCROLLBAR=0" > /etc/X11/Xsession.d/80overlayscrollbars


   Sadly the scrollbars still don’t have scroll buttons on them – which reinforces my thought that this is simply an issue with themes, and hence can probably be resolved once I’ve learned how themes work.

5. Next, move my preferred set of three window buttons back to the top right of each window titlebar by running the command:
   
gconftool-2 --set --type str /desktop/gnome/shell/windows/button_layout ":minimize,maximize,close"

6. Around now it’s probably worthwhile to logout and back in again, or even reboot.

7. Next I configured the general settings:

   1. Screen:
      Turn off at “30 minutes”
      Set screen lock “on” after “screen turns off”
   2. Power:
      Do nothing when lid closed (battery or AC)
      Don’t suspend when inactive (battery or AC)
      Shutdown if power critical on battery
   3. Time and Date:
      Panel clock to show 12hour format
   4. Removable Media:
      Tick “Never prompt or start programs on media insertion”

8. Next I added the date to the clock:
   gsettings set org.gnome.shell.clock show-date true


9. As with Unity, I configured the terminal by opening terminal preferences, and set the font to “Monospace 9″, the default terminal size to 100×40, and the scrollback to 10000 lines.

10. As with Unity, I changed the default fonts throughout:
    
gsettings set org.gnome.desktop.interface document-font-name 'Sans 10'
gsettings set org.gnome.desktop.interface font-name 'Ubuntu 9'
gsettings set org.gnome.desktop.interface monospace-font-name 'Ubuntu Mono 10'
gsettings set org.gnome.nautilus.desktop font 'Ubuntu 10'
gconftool --set /apps/metacity/general/titlebar_font 'Ubuntu Bold 9' --type STRING


11. I also removed the guest account:
    
sudo gedit /etc/lightdm/lightdm.conf

    Make it read:
    
[SeatDefaults]
greeter-session=unity-greeter
user-session=ubuntu
allow-guest=false


12. At this point I found I had a desktop that had almost all the features of my current Gnome 2 setup, plus access to the new metaphor of the Gnome Shell when I wanted it. The only problem is that when mousing to the newly added Applications menu, it’s far too easy to hit the “hot spot”, triggering the Overview Mode.

    There are extensions to move that hotspot elsewhere, but I’d prefer to change the way it works, so it takes a more conscious effort to engage it. Unfortunately there is no configuration for this, so for this exercise I took a quick hack at the base code, which is a real cludge. I’m hopeful that it may be possible to do something cleaner with Monkey patching, but for now my change proves the concept, and makes it necessary to click on the hotspot to engage it, or use the super key (as now). To do this, edit:
    /usr/share/gnome-shell/js/ui/layout.js, and change the _onCornerEntered method so it reads:

    
_onCornerEntered : function() {
// if (!this._entered) {
// Patched this to prevent the hot corner from engaging on cursor entering zone.
if (this._entered) {
this._entered = true;
if (!Main.overview.animationInProgress) {
this._activationTime = Date.now() / 1000;

    this.rippleAnimation();
Main.overview.toggle();
}
}
return false;
},


    Now just entering the hotspot will not trigger the Overview Mode – but you can still click on the hotspot (which is the top left pixel), or just use the Super key.

13. Since I was messing around in the source code I also decided to get rid of the “currently running application name” in the top panel, which again cannot be configured away. Quite why I’d need to be reminded of the name of the application I’m using is beyond me, and it takes up precious menubar space. This time, edit:

    /usr/share/gnome-shell/js/ui/panel.js, and find the AppMenuButton function prototype. Then scroll down to the “_sync” method, and make the first few lines read:
    
_sync: function() {
let tracker = Shell.WindowTracker.get_default();
let lastStartedApp = null;
let workspace = global.screen.get_active_workspace();
// Add the following line to never show the button (application name)
return;
for (let i = 0; i < this._startingApps.length; i++)
if (this._startingApps[i].is_on_workspace(workspace))
lastStartedApp = this._startingApps[i];


    This works perfectly, but like the previous code change, the problem is that whenever Gnome Shell gets updated, I would need to re-hack these changes manually. Which is not good. But as I mentioned before, I’m hopeful that Monkey Patching will come to the rescue and allow me to create a proper extension for this.

And the conclusion? Well, since it’s all written in Javascript and CSS, Gnome Shell is much easier to customise, and its extension system allows (in theory) for a robust and user-friendly mechanism to change anything that one wishes. I now have a DE that has all the features I like from an “old” Gnome 2 desktop, as well as access to all the new features of Gnome Shell. See below:

There are still rough edges, some of which are probably bugs too, but overall I can get closer to what I want (which may not be what you, or the Gnome Shell developers want) with Gnome Shell than Unity.

So when I upgrade my work “production” laptop over Christmas, it will be to a Gnome Shell based desktop.

The search for a new desktop continues

So the fight to find a workable productive solution continues. Lubuntu and Xubuntu both ended up having problems with some of IBM’s productivity applications. Not an issue for the majority of users, but critical for me. And I also discovered that IBM and Canonical have committed to work together to ensure that we “internal” IBM users of Ubuntu will get the support to ensure that our internal productivity tools do work under Unity.

Which gives me a pretty strong push back towards finding a way to make Unity somewhat more palatable and productive. So I’ve set about trying to turn Unity into something that I can live with for work. I’d not say I’ve completely achieved that yet, but a couple of (long) evenings have got me a fair way forward, and revealed a few problems that I probably need to raise as bugs against Unity – though given the non-standard way that I’ve exposed them, it’s debatable whether they’ll ever be addressed or not. Anyway, here are the results so far:

My normal desktop

Customised Oneiric, with the launcher open

Customised Oneiric, with application selector open

And this is what I did to a freshly installed Ubuntu 11.10 system to get there:

1. Add back a menu of applications that can act as a launcher, and a taskbar where I can see what I have running. I came across this post describing how to resolve these issues, and merely followed the directions.

   First the menu launcher:
   
sudo add-apt-repository ppa:diesch/testing
sudo apt-get update
sudo apt-get install classicmenu-indicator


   Once installed, run it by pressing Alt-F2 and typing classicmenu-indicator.

   Now install the taskbar:
   
sudo apt-get install tint2


   Once installed, set it to auto-run on system start, by adding an entry to the Startup Applications. The executable is at /usr/bin/tint2. Then configure the resulting bottom panel (in ~/.config/tint2/tint2rc) so it only has a taskbar, removing the clock and battery indicators, by adding:
   panel_items = T
   and adjust its size to avoid interference with the unity launcher (when it’s on screen) by making sure:
   panel_size = 90% 30
   and finally (a personal choice) remove the ability to close applications from the taskbar by setting:
   mouse_right = none

2. Next, get rid of the ugly Unity launcher by making it autohide. This is done by altering some parameters in the Unity plugin in compiz. You need to install Compiz Config Settings Manager (CCSM) first, by:

   sudo apt-get install compizconfig-settings-manager

   Then run it with ccsm, and find and select the Unity plugin. Then on the Behaviour tab:
   
   Set “Hide Launcher” to “Autohide”
   
   Set “Edge Reveal Timeout” to 100
   
   On the Experimental tab:
   
   Set “Backlight mode” to “Edge Illumination Toggles”
   
   Set “Launcher Icon Size” to 32
   
   Set “Launcher Opacity” to “0.8000″

   I still think it looks like it was designed by a child with a set of blunt crayons, but this makes it a bit more professional-looking, and since it’s now going to be hidden most of the time (and rarely used) I can live with it. I do wish there was an option to completely disable it though.

3. Next I fixed the window buttons, by re-enabling the standard minimise, maximise, close triple, and moving them to the right side of the window title bar. Do this by entering:

   gconftool-2 --set /apps/metacity/general/button_layout --type string ":minimize,maximize,close"

4. Then I disabled the ridiculous Overlay Scrollbars, and the Global Menu; together this moves the window buttons and menus back onto the windows where they belong, and gives us working scrollbars on all applications again, including those that are built on Eclipse:

   sudo su
echo "export LIBOVERLAY_SCROLLBAR=0" > /etc/X11/Xsession.d/80overlayscrollbars
echo "export UBUNTU_MENUPROXY=0" > /etc/X11/Xsession.d/81ubuntumenuproxy

   Sadly the scrollbars lack scroll buttons; I’ve not worked out how to resolve this yet, which can make fine positioning difficult. But it’s orders of magnitude easier than fighting with the overlay scrollbars.

5. Firefox has an extension to separately move its menus to Unitys top panel, and this needs to be disabled too. Access it from Firefox’s Tools->AddOns menu. It seems to require that Firefox be restarted, and a logout/login sequence to be followed before it fully takes effect.
6. Next I took back control of the workspaces, by adding an indicator applet into the notification area of the top panel, that also functions as a workspace switcher. The indicator is in a PPA, but unfortunately only for Natty rather than Oneiric. The Natty version works just fine under Oneiric, and installing it is straightforward, if a little fiddly, by following these instructions.

7. At this point I rebooted to make sure everything was working, and noticed that the classic menu indicator was not the leftmost of my indicators any more. However, it is possible to specify the exact ordering of indicators, so I reordered mine by:

   
mkdir -p ~/.local/share/indicators/application
cp /usr/share/indicator-application/ordering-override.keyfile ~/.local/share/indicators/application/


   Editing the new local ordering-override.keyfile allows the exact order of the indicators to be specified. Lowest numbers are to the right of the panel. To find the id of unknown indicators, use:
   
dbus-send --type=method_call --print-reply \
--dest=com.canonical.indicator.application \
/com/canonical/indicator/application/service \
com.canonical.indicator.application.service.GetApplications | grep "object path"


   This results in lines like:
   object path "/org/ayatana/NotificationItem/gnome_power_manager/Menu"
   In this case, the id is gnome-power-manager, but note that the command output contains underscores which need to be changed to dashes to be valid in the ordering-override.keyfile.

8. Next I installed dconf-editor, which allows a few additional tweaks to be make to Unity:
   
sudo apt-get install dconf-tools


9. I then did some configuration of general settings around the operating system. First, I configured the terminal look and feel by opening terminal preferences:
   
Set font to "Monospace 9"
Set default size to 100x40
Set scrollback to 10000


   Next I changed all the fonts throughout the system, as the defaults seem far too large:
   
gsettings set org.gnome.desktop.interface document-font-name 'Sans 10'
gsettings set org.gnome.desktop.interface font-name 'Ubuntu 9'
gsettings set org.gnome.desktop.interface monospace-font-name 'Ubuntu Mono 10'
gsettings set org.gnome.nautilus.desktop font 'Ubuntu 10'
gconftool --set /apps/metacity/general/titlebar_font 'Ubuntu Bold 9' --type STRING


   Then, in the “Screen” settings, I configured the screen to turn off at “30 minutes”, and set the screen lock “on” after the “screen turns off”. In the “Power” settings I set the system to “Do nothing” when the lid is closed (on battery or AC), and not to suspend when inactive (on battery or AC), but to shutdown when power is critically short on battery. In the Time and Date settings I set the Panel clock to show the Date and Month, and the clock in 12 hour format. Finally, in “Removable Media” I set the system to never prompt or start programs on media insertion.

10. To add a quick list of locations to the Launcher “files” icon, I ran the following as a single command:
    
echo "[Desktop Entry]

    Name=Home Folder
    Comment=Open your personal folder
    TryExec=nautilus
    Exec=nautilus --no-desktop
    Icon=user-home
    Terminal=false
    StartupNotify=true
    Type=Application
    Categories=GNOME;GTK;Core;
    OnlyShowIn=GNOME;Unity;
    X-GNOME-Bugzilla-Bugzilla=GNOME
    X-GNOME-Bugzilla-Product=nautilus
    X-GNOME-Bugzilla-Component=general
    X-Ubuntu-Gettext-Domain=nautilus
    X-Ayatana-Desktop-Shortcuts=Videos;Documents;Music;Pictures;Downloads

    [Videos Shortcut Group]
    Name=Videos
    Exec=nautilus Videos
    TargetEnvironment=Unity

    [Documents Shortcut Group]
    Name=Documents
    Exec=nautilus Documents
    TargetEnvironment=Unity

    [Music Shortcut Group]
    Name=Music
    Exec=nautilus Music
    TargetEnvironment=Unity

    [Pictures Shortcut Group]
    Name=Pictures
    Exec=nautilus Pictures
    TargetEnvironment=Unity

    [Downloads Shortcut Group]
Name=Downloads
Exec=nautilus Downloads
TargetEnvironment=Unity" | sudo tee /usr/share/applications/nautilus-home.desktop


11. Next I disabled the guest account in LightDM. This prevents someone from logging into my machine (albeit with very limited privileges) when I’m away from the machine. I suspect our security people would not be comfortable with this feature left enabled. To do this, edit /etc/lightdm/lightdm.conf, and make it read:
    
[SeatDefaults]
greeter-session=unity-greeter
user-session=ubuntu
allow-guest=false


12. Next I wanted to change the Alt-PrtSc capability, so I can capture a specific area if the screen rather than the active window. I want to retain the default PrtSc functionality. To do this, I started ccsm, and in the Gnome Compatibility plugin I changed the command “gnome-screenshot -w” (active window) to “gnome-screenshot –area”.

    While I was in ccsm I also disabled the “Snapping Windows” plugin, as it was driving me nuts. I also set a key combination (Ctl-Alt-g) on the “Toggle Handles” option of the Unity MT Grab Handles plugin, to allow easier screen grabbing & manipulation, as the default theme has quite small borders to its windows.

13. By default, Oneiric doesn’t come with any screensavers. It simply fades to black. Which is efficient, but rather boring. So I removed the default screensaver (which does nothing) and reenabled all the pretty screensavers:
    
sudo apt-get remove --purge gnome-screensaver
sudo apt-get install xscreensaver xscreensaver-gl-extra xscreensaver-data-extra


    It’s then necessary to add “xscreensaver -nosplash” to the startup applications. This is the server portion of the screensaver which does the actual displaying of the animations, the locking of the screen, and any power management. It’s configured with “xscreensaver-demo”, which allows graphical selection of screensaver animations etc. Finally, to keep the ctl-alt-L key combination to manually start the screensaver, it’s necessary to:
    
sudo ln -s /usr/bin/xscreensaver-command /usr/bin/gnome-screensaver-command


14. Getting Conky installed (to create the animated desktop) was simple, once I’d realised that the key to making it work under Unity is to change the .conkyrc configuration stanza to own_window_type normal. However, Unity does something odd with painting itself into a different window than the root, so Conky cannot do transparent without help from something like feh, but that can only work with static images, not my preferred gradient fill. I resolved the issue by adopting an image for my desktop background.

15. Finally, I mentioned a few issues that I’d not resolved yet:
    
    It seems impossible to stop the Unity top panel showing the name of the active applicaton.
    
    It seems impossible to move the classicmenu_indicator to the left of the Unity top panel.
    
    Having disabled the overlay scrollbars, the remaining scrollbars lack scroll buttons
    
    It seems impossible to remove the workplace switcher icon from the Unity Dash (hard-coded) Raised as Bug 898230.
    
    It seems impossible to remove the Dash Home icon from the Unity Dash (Hard-coded) Raised as Bug 898230.
    
    When maximising a window, Unity still steals the window buttons, and places them in its top panel Raised as Bug 898250.
    
    When stealing the window buttons, it doesn’t adhere to the setting in gconf for how to display them, but uses a hardcoded default Raised as Bug 898250.
    
    Seems to be impossible to completely disable the Unity Launcher Raised as Bug 898260.

    Help with any of the above would be much appreciated!

The search for a new desktop

As I mentioned here, I’m less than happy with the move Ubuntu have made towards adopting new desktop environments that seem to be more suited to touchscreen devices than desktop computers. So I’ve been test-driving a few of the alternatives to try to find something that will let me get on with my work, without getting in the way all the time.

So far I’m very impressed with LXDE, which is available pre-packaged onto the underlying Ubuntu 11.10 base as “Lubuntu”. Admittedly it’s very basic out the box (or off the USB key), but that seems to be because it’s been designed for very low-powered or old computers. All the default applications have also been selected to keep memory and CPU usage to a minimum. Nothing wrong with that, but in my case, I have a ridiculously powerful laptop with lashings of disk and memory to run it on – so all I want is the good old fashioned desktop metaphor back. Lowered system requirements are simply an added benefit.

So I’ve gone about hacking Lubuntu into something better suited for me. So far I’ve removed sylpheed sylpheed-doc sylpheed-i18n sylpheed-plugins mtpaint osmo xpad ace-of-penguins abiword abiword-common libabiword-2.8 gnumeric and gnumeric-common. That got rid of most of the default applications, and makes way for me to replace them with something fuller-featured.

I then added thunderbird xscreensaver-data-extra xscreensaver-gl-extra recoll inkscape scribus gimp gimp-data gimp-data-extras gimp-help-en gimp-help-common dia shotwell libreoffice aisleriot gnome-sudoku freemind audacity musescore easytag pitivi and conky-all. That adds most of the applications that I would expect to need from the standard Ubuntu repositories.

I then reconfigured the panels. Lubuntu comes with one panel on the bottom of the screen, a la Windows XP, but I’m used to the Gnome approach. So I moved the original panel to the top of the screen and added a second panel to the bottom. I then reconfigured the panels to match what I’m used to in a Gnome 2.x environment by moving around the various panel items – which was far easier than configuring the Gnome panels. So far so good.

Interesting to note that at this point, my test laptop (which is “only” a dual core 2Ghz machine with 2GB of ram) absolutely flies. But I still have a lot of things to try:

I know it’s just eye-candy for the sake of it, but I tried to add a simple Conky installation, showing some key facts and figures to the desktop – date/time, CPU, RAM & disk monitoring etc. It turns out that Conky and LXDE’s FilemanPC (which manages the desktop) don’t play well together out the box. You can get Conky scripts roughly working by altering them to contain “own_window_type normal” rather than “own_window_type overlay” or “own_window_type desktop”. However, the window can easily get minimised, with no way to recover it. Low priority, but more research required on that.

Currently most of the Thinkpad Fn-F1-12 key combinations aren’t recognised. The only one I really care about is Fn-F4 for suspend, which I can workaround using the menus, but I’d like to get at least that one enabled.

Next I need to test all the IBM-specific software that I normally use. I suspect that there may be some issues around the support of some of the Lotus products, which are built on top of an Eclipse base, and hence may not play well with my different desktop environment. Time will tell on that, but its critical for me.

Finally, assuming I can get all these basics working, I think I’ll be looking into producing a custom theme, as the standard Lubuntu (cold) blue isn’t at all to my taste.

Ubuntu losing its way?

As you can probably tell, I’ve been a fairly ardent supporter of Ubuntu Linux for several years now. I run it on all my machines here at home, and on several machines at work, including my primary workstation, a Lenovo X201 laptop.

It’s served me really well; every six months a new release has brought me a better, more reliable alternative to Microsoft’s Windows, with better support for my hardware, better pre-installed applications, and better usability.

It’s been so good that I’ve been able to eschew the IBM standard Windows software stack, and avoid the rather slow-to-evolve Redhat-based desktop that IBM has been promoting amongst it’s more technical community. Living on the bleeding edge with Ubuntu has been surprisingly easy.

Sadly, with the last couple of releases, that has been changing. Ubuntu seems to be going it’s own way, with a new graphical user interface (GUI) called Unity. Adopting it seems to have involved a lot of changes for changes sake. We’ve suddenly had the window controls moved from the right to the left. Now the window controls aren’t on the window at all – they’re on the top panel. And it’s design looks like something designed by a 6-year old with a set of crayons.

It might work well for people on a touchscreen netbook or smartphone who want to do nothing more challenging than check their email, but on my laptop, which is often docked to multiple high-resolution monitors, where I want to have a couple of dozen windows open at once, well, frankly it’s an unproductive mess.

I’ve tried to change my way of working. To adapt. But it just isn’t possible to do what I need productively. It just doesn’t work. I’ve also tried Gnome Shell, which is the other readily available GUI in Ubuntu 11.10. And it’s just as bad, probably because it’s very similar to Unity.

So with a heavy heart I’m getting ready to move on. The trouble is, what to? Gnome and KDE are both mired in the same “innovative new desktop metaphor” game as Unity. Which only leaves me with some of the niche desktop environments like LXDE, XFCE, CDE or maybe even Enlightenment. LXDE or XFCE are my most likely choices – they’re both similar to the old Gnome 2 desktop in ethos, but nowhere near as polished in their implementation.

Or my other option is switch back to Microsoft Windows 7, or to move on to Apple.

It’s not my preferred option, but I need my computer to work. It’s a tool, not a philosophical or religious debate; I need to be productive, to satisfy my customers, to earn money to pay the bills.

Server drive failure

In other news, I received a barrage of emails from my home server the other day, each complaining about a degraded raid array. A swift check through the emails indicates that every array on the machine had been degraded, and a little more investigation leads to the simple conclusion that one of the hard drives has completely failed.

So far I’ve not had time to check if this is a failure of the drive, the controller, or perhaps even just a cable coming loose, but it’s nice to see the server continuing to function completely normally despite this failure. Lots of kudos for the software raid functionality in Linux.

My job for tomorrow morning is to find out what has actually failed, replace it, and then reinstate the degraded raid arrays. One thing I’ll look into is getting SMART monitoring of the hard drives enabled. Currently it isn’t, and it would have been nice to have had some advance warning of this so I could have had the new drive ordered and waiting.

Still, hopefully the whole thing is not more than a couple of hours work.

Update: Initially it seemed like a cabling problem; simply replugging all the drives seemed to resolve the problem. However, putting it all back together again caused it to stop working again. After quite a lot of swapping of cables, and then finally wiggling of cables, it became clear that the problem was the drive after all. Ultimately it looks like the circuit-board attached to the drive has failed. Flexing the cables causes a little bit of movement of the circuit-board, which I suspect over time has caused it to fail.

A new drive seems to have completely resolved the problem. Having got that installed, it took about 5 minutes to partition it up, another 5 minutes to add the partitions to the raid sets, and about 4 hours for the linux software raid system to rebuild the raid sets.

And all is now working perfectly again.

Ubuntu 11.04 Alpha 1

I needed to reinstall my development system today, so I dropped the first Alpha code release of Ubuntu 11.04 onto it. It installs cleanly enough, but the move to the Unity graphical interface is not at all to my taste, and at the moment the classic Gnome interface isn’t functioning reliably.

Given that I’m not actively developing Ubuntu I think it’s probably just too early in the cycle for me to be sensibly using/testing it.

For now I’m going to revert back to a fresh install of Ubuntu 10.10.

Bitten by a Viper

In this case, the viper in question is an old industrial control computer, based on an Intel PXA255 processor, in PC104 form factor, running a minimal linux. It was originally manufactured by Arcom Ltd, who have in the intervening years been taken over by Eurotech S.p.A. and comes with a nice complement of default communications options.

Mine is a standard “full-fat” Viper board, with no additional expansion cards, but mounted in an industrial enclosure with an integral UPS battery-backup. Sadly it’s been lying around gathering dust in my study for about the last 5 years, and as part of a recent attempt to tidy up some of my clutter I decided I either needed to make use of it, or get rid of it.

A little searching unearthed the power supply, and then, according to the little red LED on the back panel, we had life.

The first problem was how to talk to it. This is a true industrial device – no screen or keyboard. The options are either to telnet or ssh in over the network connection, or use an ASCII terminal over a serial connection. And therein lay the first problem; it didn’t connect to my network as I was expecting, leaving only the serial option open to me. But as I’m almost exclusively laptop-based these days, finding a machine with a serial port, and then a serial cable to link it to the Viper, took quite some effort.

But having done so, and set up minicom with the correct serial port parameters (helpfully documented in the Viper manuals) I was able to login to the Viper, at which point a little debugging of the network stack revealed the issue – at some point I’d defined the Viper with a static IP address, on a different subnet to my current home network.

A few quick edits to return it to DHCP operation, and a little configuration work on my home servers dnsmasq configuration returned the Viper to my home network, at a readily accessible IP address, allowing me to ssh in again.

At this point, having proved that the system is working again, I now need to decide what to do with it; and in this case, I’m going to use it as part of my plan to implement a set of DIY ambient orbs, as I mentioned back in this post. The Viper happens to consume only 9w while network connected, and has a built-in I²C interface, which can connect to BlinkM LED’s which I can mount in my B&Q Cubo housings. This will allow me to control the colour of the orbs from a program running on the Viper.

Better than that though, I can then install an MQTT client on the Viper, allowing my Viper program to subscribe to a topic on my home servers MQTT micro-broker. This will allow me to have the Viper change the colours of the orbs in response to messages published to the broker on my home server. At that point I can trivially integrate any sort of external input to the orbs just by administering my home server, & without needing to make further updates to the Viper.

So all I need to do now is to get the AEL development kit (cross-compiler etc) set up so I can write some code for the Viper, and then buy some BlinkM LEDs. Which sounds simple, but unfortunately the AEL development kit hasn’t been updated for some 4 years now, and isn’t keen on installing on my latest and greatest Ubuntu 10.10 development machine. I’ve put some calls out to colleagues who have also had experience with these Arcom Vipers, but so far no joy. Next step will be to see if Eurotech can provide a little help – after all, I suspect the original Arcom engineers will mostly still be working there. I guess the worst case will be to set up a *really* old Linux system in a virtual machine, and install the AEL development kit on that instead.

Scanning under Ubuntu 10.10

I acquired an old Canon Canoscan N650U USB scanner recently. These date from the turn of the century, so I plugged it into my Ubuntu 10.10 system “on the off chance it might still work”, and to my surprise it (a) was immediately recognised by Ubuntu, and (b) still works perfectly.

The “Simple Scan” application included with Ubuntu is limited to the essential options, and is none the worse for that. You can crop the scan area, change the resolution, and select between text and image scan types, but that’s it. The resulting scan can be saved as one of JPEG’s, PNG’s (which can be rather large) or PDF’s.

Maximum supported resolution at the application level is 2400dpi, which is about half the marketing claims for current generation USB scanners, but oddly a lot more than the 600x1200dpi optical resolution claimed by the 650U’s specifications. I’m guessing the hardware does some interesting interpolation to produce the higher resolution output, which makes me wonder if best results might be obtained by setting it to 600dpi or 1200dpi? Either way, the results seem more than adequate for my needs so far. It’s certainly looks “good enough” from the scans of text documents and photo-type images that I’ve done so far, and ought to let me do simple one-off “photocopying” if I need to.

What I’d like to do next is find a simple OCR application that can work in tandem with the simple scan application to produce plain text output. There seem to be several OCR offerings that work under linux, but it’s clear that none of them are integrated into the basic system in the same way that the scanner support is.

A little more investigation is required.

Wacom Bamboo Pen tablet under Ubuntu 10.10

I bought one of these USB graphics tablets for my daughter for Christmas. It turns out that it’s not quite plug and play on her Ubuntu-powered netbook – well, not until a few extra commands have been entered in a terminal:

sudo add-apt-repository ppa:doctormo/wacom-plus
sudo apt-get update
sudo apt-get install wacom-dkms

After this the tablet is hot-pluggable, and acts (at least initially) as another mouse-like device. I’ve yet to try it with tablet-aware applications like Inkscape or The Gimp, both of which will need a little additional configuration to recognise and make use of the advanced features of the tablet (pressure sensitivity etc) but it’s looking good so far.

A little playing with the configuration of The Gimp has proved that the tablet works perfectly; we now have detection of pressure working, allowing the rendering of variable stroke-width depending on the pressure applied to the pen. All in all I’m very impressed – having had the opportunity to experiment a little, I’m now wondering if I could use one to create free-hand drawings in presentations, which I suspect could be very effective.