Random thoughts about geeky stuff…

While the Debian boot team works hard on releasing the second beta of the Debian Installer here are some facts you probably didn’t know about the Debian Installer:

• You can install Debian with a kickstart file - this is done via the kickseed package.
• The Installer will automatically install and configure sudo if no root password is provided - implemented in d-i/user-setup
• For installing systems with multiple NICs via pxe you can use ipappend 2 in your pxelinux.cfg to automatically determine the appropiate network interface.
• You can setup the Debian Installer to automatically start an ssh daemon to control your installation - see netconsole for more details.
• If you are using netconsole the installer can automatically download ssh keys from a specific URI. This can be useful for deploying ssh keys in virtualized environments like EC2. For more details about this feature have a look at #592550.
• If you specify bubulle or tbm as your realname the installer will automatically change it to the realname of the Debian Developer.

While reading planet.debian.org I discovered Why the name via Christian Perrier.

There are some great gems on Why the name like:

• dd: on IBM system/360 mainframes, the Job Control Language used a dd-like syntax to create a Dataset Definition
• eclipse: (Java IDE) the Eclipse Foundation may be essentially a project to support Java development in a Sunless environment, but when it was named the thing it was intended to eclipse was MS Visual Studio - the snub to Sun Microsystems is an accident
• fvwm: nobody knows what the “F” stands for, but the most popular arbitrary retrofit is that it’s the “feline” virtual window manager.
• haserl: lightweight CGI wrapper system; a Bavarian word for “bunny” (so another semi-arbitrary animal)
• mkfs.bfs: a tool for creating SCO UnixWare boot file systems, useful because… EXCUSE NOT FOUND
• yelp: formerly gnome-help, now inexplicable. Did the word “gelp” get written in hard-to-decipher handwriting, or what?

When I first started with Linux I also started to use vi. This was ages ago bug ever since I was hooked and used vi and later vim extensively and liked it a lot.

I first encountered Emacs while participating at a local student research center and was really impressed by the features (especially AUCTeX and the possibilities to customize but didn’t really switch as many systems I had access to didn’t have Emacs installed nor was I really interested as I had a pretty extensive ~/.vimrc.

Fast forward multiple years later - I worked with a great colleague and friend of mine who not only used vim, zsh and a tiling window-manager (like I do) but Emacs as well. After I saw him using both editors proficiently and talking about his ~/.emacs (he had basically no configuration for Emacs) I decided to start using Emacs on my own.

And I loved it. Not only is Emacs really flexible (e.g. Tramp, Org mode) but it also looks like the development happens at a faster pace. It seems like modules get integrated into Emacs more often than with vim but there are also some pretty cool packages like rainbow-mode, google-maps or Mumamo.

Nowadays I mostly use Emacs and just use Tramp to edit files via ssh or run them on a remote server. But every now and then I still use vim for quick edits or changing small things even though I am still practically an novice with Emacs.

If you already know vim look beyond one’s own nose and have a look at Emacs and vise verca. Both editors have great qualities and it is not an accident that both are really dominant.

In light of the recent discovery of the Leap second bug in Linux some NTP Servers seemed to announce a wrong leap second. This is a rather cool and intriguing way to attack a large quantity of Servers and trying to cause a Denial of Service or increase the power bill.

As not all all systems received the latest patches (the next leap second wasn’t announced yet, so no need to rush…) there are still vulnerable systems around and some probably were affected.

See http://serverfault.com/questions/403732/anyone-else-experiencing-high-rates-of-linux-server-crashes-during-a-leap-second for more details about the problems associated with the leap second bug and how to mitigate and fix the problems.

RFC 952 as it’s predecessor RFC 1123 describe the allowed characters in an hostname. The defintion from RFC 952:

 <hname> ::= <name>*[“.”<name>]

 <name>  ::= <let>[*[<let-or-digit-or-hyphen>]<let-or-digit>]

This means a hostname has to start with a letter and can only contains letter, digits or hyphens. With RFC 1123 a hostname can also start with a digit.

Most resolvers don’t allow to resolve/connect to an invalid name, e.g. one with an underscore. Even though some support invalid hostnames like Windows some applications will have problems, like Internet Explorer with cookies.

An workaround is to specify the entry in /etc/hosts - it may also help to add to specify

options no-check-names

in /etc/resolv.conf

After more than two years of ignoring my old blog and many changes in my life i decided to start a new blog and try to write regularly about things I do or encounter. For now this is mainly a playground to write down my thoughts and link to interesting or fascinating stuff I encounter while working.

I am looking forward to this journey and hope I’ll provide insight and new ideas.