Friday, November 23, 2007

Fun with RFC:s

As you may know RFCs (Request for Comments) published by IETF (Internet Engineering Task Force) include specifications for the most common protocols and formats used on Internet. You have IP, TCP, SMTP for mail, HTTP etc.
Among these RFC:s there are some that are not too serious, like the ones published April 1:st. Today I found this site that guides you to the more humor typed RFC:s.

Thursday, November 22, 2007

Sysklogd is the bad boy

Back at the computer today I have found out that it is sysklogd that is the bad boy on my Ubuntu 7.10 (Gutsy Gibbon) server. What happens is that sysklogd makes the some later scripts (dbus or bind9) started during boot is hanging. Some what irritating. It seems to works fine when starting it later. For instance. If I start sysklogd after the computer has booted and then restarts bind. Bind starts correctly.

For now, I start it manually after boot. I will do some more investigations what is happening.

Tuesday, November 20, 2007

Something got terrebly wrong

I upgraded my server to Ubuntu 7.10 (Gutsy Gibbon). Everything looked fine during the upgrade and it booted smoothly, but I could not log in and it did not answer on ssh.
It looked like it did not start any services. I booted in single user mode and there I could start the services like bind and ssh. After some testing I noticed that some of the early services blocked or locks the later ones.

I assume it is either acpi or dbus that is the bad guy. I also assume that the root cause of the problem is that I am using a VIA mini-itx board with a VIA-processor. For now, I have booted in single user mod and started all necessary services and will dig in to the problem some other day.

Sunday, November 18, 2007

Blutooth and Ubuntu

I bougt a new mobile phone yesterday, a Nokia 5300. Now I tried to connect the phone using bluetooth from my Ubuntu 7.10 (Gutsy Gibbon). It worked right out of the box.
I made my phone visible. Right clicked the bluetooth icon on my Ubuntu desktop and selected browse device. The phone appears in the list, select it. Then the phone asks if you want to connect to the computer and for a pin code. Give any 4 digit number. After that the computer asks for the same pin code. Then you can browse your phone using Nautilus.

Wednesday, November 14, 2007

Service and /etc/init.d

Christer Edwards asked in his blog today about the difference between starting a init-script through /etc/init.d and the command service that exist on at least Red Hat boxes. I left a comment on his blog, but thought it would be nice to write some more about it here. It is not the first time I got the question.

What Christers blog was about was that you can get the service command on Ubuntu too:
sudo aptitude install sysvconfig

At boot of your Linux machine the scripts in the /etc/rcX.d are started. X corresponds to your run level. On clients is it normally 5 and servers 3, but all Debian and Ubuntu-boxes uses 2. Anyway, those scripts are actually links to /etc/init.d/. The software that has called these scripts has traditionally been init, now days it is upstart on Ubuntu. Init does not necessary have the same environment variables set as you will have when you log in as root. Therefore is the service command fix so that the environment variables are the same as when starting the services on boot. Starting a service throug /etc/init.d does not guarantee that, i.e. a service starting when you loged in as root may not start at boot since some variables are missing.

Sunday, November 11, 2007

How to find the interesting TV shows?

I have had the possibility to do some coding this weekend. Which also gave me the possibility to learn XSL(T) , look closer on iCal, and xmltv. The result is a small application to search TV charts including the descriptions of the TV shows. It uses xmltv to fetch information about whats on TV. Then there are a very googly search interface to find the interesting shows. Out comes a new reduced XML file in the same format as xmltv but only including shows that match your search. This XML-file can then be translated to either HTML or iCal using XSL. Its is of course possible to write other XSL-files to create other formats. It is written in Python.

I am not ready yet to publish the application. It needs some documentation and packaging. My main reason was not to write the program, it was more about to play with different algorithms and programing techniques. The program was just a side effect.

I will write more about this software when I am ready to publish it.

Saturday, November 10, 2007

Don't write another line code until you have seen this

I think this talk is one of the best talk I have found in Googles Engineering series. Google talks are generally very good, but this is even better and has a good speaker.



Joshua Bloch talk "How To Design A Good API and Why it Matters" presents a lot of good information what to think about when creates API:s. Even if you aren't writing another framework it is important. I think people seems to believe today that reuse can only be done using frameworks. Joshua points out the importance of good API:s inside your program and for different modules.

I would also like to add that this is important when designing new XML-DTD:s, which is a kind of API. For instance, I have seen XML file formats that says the address-tag includes space separated e-mail addresses. Why not use multiple address-tags, one for each address. In this way I can solely use my XML-parser to parse the file and do not need add extra code to separate the sting at spaces.

If you do not have an hour at the moment, remember this points which I have taken from the talk:

  • When in doubt, leave it out
  • Don't make the client do anything that the module could do
The paper he gives away he says is from the abstract from OOPSLA so I assume it is this abstract he means. I like rule of thumbs in this format.

A very good book on the same topic is "Object-Oriented Design Heuristics" by Riel.

Friday, November 9, 2007

Piglet meets Gutsy

My wife is in London right now so I took the opportunity to upgrade her laptop Piglet (a Zepto 6014w) to run Ubuntu 7.10 (Gutsy Gibbon). It worked smoothly and Compiz is working great. The upgrade took less time than the roast I had in the oven.

It is actually quite boring to write about this since it worked too well. No problem and no surprises. the lack of surprises mostly depends on that I have been using Gutsy for a while on my laptop.

Thursday, November 8, 2007

Zepto sells on of four without OS

According to the Swedish computer newspaper TechWorld OpenSource (article in Swedish) the Danish Laptop provider Zepto sells one of four computers without operating system. My wife bougth one half a year ago. It works terrific with Linux, in her case Ubuntu. I would not hesitate to buy my next laptop from them. Zepto sells computer on mail order all over Europe.

I do not understand in what the major computer providers sees the problem. May be I do, it is called Microsoft.

Open Source Forum 2008 continued

As I wrote the other day I have visited the Swedish conference Open Source Forum.

It was a talk about buying the right thing after lunch the first day. All he said were things that everybody knows; focus on the functionality you need, do not buy a lot of extra functionality, more expensive is not better etc. It is always good to repeat those things. I still wounder why so many organizations pay for extra functionality they do not need.

The IT manager of the small city Osby then told us that they have converted their organization to Open Office. Those who needs the MS Office functionality can get it but its become more and more rare. Unfortunately the big suppliers of applications to governmental organizations integrates very close to MS Office and are unwilling to change that. I have talked to several cities that want it to change, but failed.

The second day became more technical focused with talks about PostgresSql/EnterpriseDB, Ubuntu, Thin clients based on Ubuntu, Security and Intel and Sun's Open source strategies.

I was surprised that a lot of talk mentioned Ubuntu, beside the two talks about Ubuntu. In the talk about thin clients Anders Wallenquist presented how LTSP works. I have actually never looked at it before, but it is quite impressive. Notable is that, based on questions from the audience, people have a very vague understanding of what Thin Clients are and how they work.
Urban Anjar from the Swedish LoCo team presented Ubuntu in a more broad perspective and what the Swedish LoCo team does. I must say I would like to see a merge of the two Swedish sites ubuntlinux.se and ubuntu-se.org.

There were also a lot of talk about Xen and virtualization.

One fun thing was that two independent people introduced me to other people as "Open Source and Linux pioneer in Sweden". It is a bit to stretch a point in my opinion but I may be one of the first to advocate and demonstrated the use of Open Source in classic organizations due to replace legacy systems.

Tuesday, November 6, 2007

Open Source forum 2007

I am currently attending the Swedish conference Open Source Forum 2007 in Stockholm. The conference have prior years given a good view about what happens in the aspect of use of Open Source in Sweden with some minor part from other countries.

So far the national property board have presented what Open Source they use, which is a lot. The most interesting is that they use Samba and open ldap instead of AD. One talk as about GPL v3 in a Swedish perspective. The last seminar was about about Peugot and Citro├źns client use of Linux (Noviell) clients. They will have 20000 in the end of next year. Their users demands that they want Linux, which is a very good response.

The lunch is ending.

Saturday, November 3, 2007

In search for rescue

A friend called me this morning in an urgent need for a rescue CD with support for EVMS, LVM2, and JFS. A lot of rescue CD:s lack in either EVMS or JFS. I did some search and found System Rescue CD. It looks like it full fills the requirements and much much more. I think I have used this rescue CD in an earlier release.

Friday, November 2, 2007

Finally IMAP support at GMail

The only complain I have had against Goggles GMail have been that it did not support the IMAP protocol. Now it does! And it works great together with Evolution. Thank you Google!