Unison – Secure synchronization of 2 computers

When not writing on my blog I am doing my master thesis in physics at the Niels Bohr Institute in Copenhagen. At the university I use my subnotebook and at home I have a more powerful desktop with a bigger screen. I would like to have the file systems synchronized both considering the convenience and the security of not having the data on one disk only.

There are many ways to do synchronization including home brewed rsync scripts, CVS, SVN and more, but I wanted something that was easy to setup, so I chose Unison. One of the great things about Unison is that it is very easy to use and supports SSH – the latter makes the synchronization secure even over the dangerous internet (unlike FTP). Furthermore Unison supports both Windows, OS X and Linux and even supports syncing a Linux folder with a Windows folder. The setup much more easy than using CVS and SVN which makes unison the right choice for most users. CVS and SVN also need to be notified when new files are added to the project but this is not necessary with Unison.
Continue reading Unison – Secure synchronization of 2 computers

Autofs and sshfs – the perfect couple

What is sshfs and why is it so great?

sshfs is a file system in userspace (FUSE) and can be used to mount a remote ssh account locally in a folder. This is absolutely great – If I need to work on files from my server I can use the simple command:

tjansson@dirac:~$sshfs tjansson@bar.com: sshfs/

which mounts the remote file system on bar.com over a encrypted connection to the folder sshfs/ – none of the programs is aware the files are remote and working on a file in the folder sshfs/ is the same as for local files – at least if the connection is fast enough.

What is autofs and what why is this even better than plain sshfs?

The great thing thing about autofs is that the line above is no longer needed. The mounting of the remote file system is done in the moment I try to access the folder by the autofs daemon. sshfs and autofs together makes a encrypted remote file system available to the user and the system in a totally transparent way. Once the setup is complete the user will never need to know that the files are actually on a remote server.
Continue reading Autofs and sshfs – the perfect couple

KDE 4 – Screencast and first impressions

Like most geeks I needed to see the latests and greatest as soon as possible. So I downloaded the KDE 4 iso file from Kubuntu’s page and mounted it in VirtualBox to see what it was all about. I created this blog story to save some fellow geeks the time of downloading and Virtualboxing. The result can be seen as a screencast I made with Istanbul. You can download it here:
kde4.ogg (8.2 mb) (4 min. 20 sec.)
If you are not in yet a Linux user this format will maybe be unknown to you but it can be viewed with VLC among many other capable viewers.

Continue reading KDE 4 – Screencast and first impressions

Presentations with LaTeX beamer class – KU style

Impressive presentation using pdf and pythonWhat is LaTeX beamer class?
The Beamer class is used to make presentation in LaTeX. This gives you the power of regular LaTeX with great math rendering and a easy support of vector graphics into your presentation. Beamer class presentations appear very structured when compared to the common PowerPoint presentation in my view.

This small article does not aim to learn anybody how to use beamer but merely to present to examples which can be hacked. Underneath each of pictures the code and the PDF is presented.

Two recent presentations made with Beamer
In this fall I made two presentation using Beamer. One for physics students about to pick the subject for the bachelor project and one to present a topic of choice for everyone interested.

Download presentation: roterende-vand.pdf 16.9 mb (24 pages)
See texcode: roterende-vand.tex.html

Continue reading Presentations with LaTeX beamer class – KU style