Authenticating an Ubuntu PC to Active Directory

Saturday, March 22nd, 2008

Likewise Open is a piece of software designed to make it easier to integrate Linux PC’s into an Microsoft Windows Active Directory (AD) domain. Now you can log onto your Ubuntu PC using your Windows network username and password, and access your shared files and resources whilst logging on only once.

You can find the ‘likewise-open’ and ‘likewise-open-gui’ packages in the Ubuntu Hardy universe repository. Go to System > Administration > Synaptic Package Manager, ensure the universe repository is enabled, and search for ‘likewise’.

After installation, you can find the Likewise Open GUI in Applications > Internet > Likewise. Joining the domain is simple enough. Specify the FQDN of your domain and click on ‘join domain’. After giving details of an account with permission to add computers to the domain, you should be connected.

Restart the PC, and at the GDM login screen try an Active Directory login. For instance:

DOMAIN\username

Hopefully all should be well, if not try the following.

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Login as a normal (non-AD) user and run the following command.

lwiinfo -n “DOMAIN\username”

You might get an error complaining ‘could not obtain winbind separator!’

It looks like the likewise-open script is not set to start with the system. To see if this is the case, try running ‘sudo likewise-winbindd -start‘ and try the command again. If it works this time (you should see a string of numbers and letters) you need to set likewise-open to start with the system.

To do this run ‘sudo sysv-rc-conf‘ from the command line, and turn the likewise-open service on for runlevels 2,3,4,5. Hopefully this should be sorted soon, I’ve filed a bug report.’

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At this moment in time you are likely to come across other issues. Sound, USB, sudoers etc will not work under the AD user. I’m sure that there are workarounds for this which involve mapping AD user groups to local groups. Hopefully in time for release we’ll see some firm instructions for this appear.

If you’re interested, watch this space.

Why Ubuntu Needs to Charge for (some) Software

Monday, February 18th, 2008

Now before you fire up your trusty keyboard to shoot me down in flames for suggesting this. I want you to think about the continuing challenges that Ubuntu (and Linux in general) face as they compete against Microsoft for a share of the desktop OS market.

A good place to start is here, at a Slashdot article entitled ‘Why Linux Doesn’t Spread – the Curse of Being Free’.

You see people just don’t trust things that are free. They have been conditioned to believe that ‘you get what you pay for’ and hence find it hard to see the value of free software. As the article rightly points out, as far as Joe Newbie is concerned both Windows and Linux are free to him, so he will have the one worth $300 thank you very much…

If you read through the comments of the article you come to another observation. Lets assume that Joe Newbie has got Ubuntu installed on his laptop. He opens up his favourite .mp3 album on the PC and gets a prompt for a codec. Now although Joe is a newbie, he knows that .mp3’s work fine out of the box on Windows so why not on Ubuntu? Uh-oh! His mistrust of Ubuntu increases.

OK, so what can we do about it?

Well, if you’re observant, you will have noticed that we now have an all free software version of Ubuntu. Every single piece and parcel of it is comprised of free software. Great eh?

Why not also create an Ubuntu variant which includes (out of the box) support for things like .mp3, dvd, wmv et al and charge for it? Canonical could license the technologies needed to legally create such a piece of software and sell it to the customer.

As long as the price was kept reasonable, Canonical could sell a ready to rock, fully spec’d up operating system to OEMs. It could also sell a boxed retail version to the public (although of course these sales wouldn’t be as large) through distribution channels such as PC World or Amazon. Chuck in six months technical support helpline access for a few quid and you provide a support channel for the punters too!

I think that if Canonical could do this, Ubuntu would become more credible in the eyes of the ignorant computer user and we just may be able to entice him across…

Creating HDR Images in Ubuntu

Sunday, January 20th, 2008

Wikipedia tells us that “high dynamic range imaging (HDRI) is a set of techniques that allows a greater dynamic range of exposures (the range of values between light and dark areas) than normal digital imaging techniques.”

Phew…

Chris ‘o’ pedia would read something more like “HDR images look really cool. You can make pictures that look kinda neon and freaky, a bit like giving your digital camera an acid tab. What’s more you can create them using Ubuntu Linux – for free!”

All you need other than a digital camera and a computer with Ubuntu installed is a piece of software for creating HDR images. As luck would have it, there’s one in the Ubuntu repository. It’s called Qtpfsgui. Go get it!

sudo apt-get install qtpfsgui

Whilst you’re installing software, you may as well have a method of lining up your photos ‘just in case’ they don’t come out quite as you wanted.

sudo apt-get install hugin hugin-tools

OK, first of all you’ll need some images.

Take your camera and shoot a series of images with a range of exposures. You can do this by decreasing/increasing the shutter speed, aperture or using the ‘bracketing’ mode on your camera. Check out Wikipedia’s article on Exposure Value for more info. The important thing is to get a good range of exposures which show the bright and dark features of the shot you’re taking.

Now you have a few images, simply open Qtpfsgui, create new HDR, load all of your images in (I used 12 for mine but you don’t need that many) follow the wizard then select Tonemap HDR.

Try the ‘fattal’ algorithm, it seems to create the most striking results.

If you want to look at some really great HDR images or find out more about Qtpfsgui then check out the Qtpfsgui group on Flickr. In fact, if you really want to get into creating HDR images you need to do some research and this Flickr group is a good staring point.

Finally, here’s my attempt at creating a HDR. The subject is a little boring but all I could conjure up this evening!

Have fun and post back here to show me your efforts!

Light in the Living Room - HDR Test