I have been buying some music on itunes, it comes in AAC (.m4a) format, which is great to use in itunes (I have it on a Windows 7 running over VirtualBox), or to use it in my iPod Touch or iPod shuffle, but if I want to use it in my cell phone (an old one which does not support AAC format) I have to convert it to mp3, I have to also convert it if I plan to use mpg123 which I use a lot.

Well lets go to learn how to convert from AAC to MP3

It may happen that you have send a real big job to the printer, and then you realize that, you forgot to change the paper size from A4 to letter, or any other scenario where you may need to change something in a document already sent to the printer queue, so now you need to cancel it.

Iptables, is a great tool to create firewall in Linux, actually it is not only for that, but useful to pre-process or post-process any package of data that arrives to our Linux Operating System machine.

The other day I was needing to block the access to my network using the mac address of a machine, and Iptables come to save my day.

This is my scenario, I have an open Access Point (Do not never do that, always keep your access points closed, using WEP or better WPA, or mac address filtering).

I have just wrote a post about how to install nslookup, but what is nslooup?

well, according to wikipedia it is

"nslookup is a computer program used in Windows and Unix to query Domain Name System (DNS) servers to find DNS details, including IP addresses of a particular computer, MX records for a domain and the NS servers of a domain. The name nslookup means "name server lookup". The most common version of the program is included as part of the BIND package. More modern alternatives to nslookup are the "host" and "dig" programs which also ship with BIND. Both nslookup and dig look up nameserver information from /etc/resolv.conf."

If you work with Ubuntu, Debian or Fedora, as soon as you have your default installation, you will probable have nslookup utility installed, but, if you are like me, working on Arch Linux, you will have to install it.

Just enter this.

sudo pacman -S dnsutils

And you will nslookup and other dns utilities ready to run.

If you are usually on the move, and you need quick access to your Linux server, you may buy a Nokia Symbian phone, E-series, N-series, and others like 6120 classic are useful, and you can then install Putty for Symbian on it and from there access to your Linux box.

Here are some screenshots of Putty for Symbian in action.

Almost all major GNU Linux (operating system) distributions comes with inetutils installed by default, but that is not the case with Arch Linux, and maybe Gentoo as well.

If you are running one of these distributions, you may miss the command line

You may know that if you have a directory called

My-Documents

and you want to change to it, you have to do something like this

cd My-[TAB]

And you will end with the full command like this.

cd My-Documents

But, if you do this

cd my-[TAB]