I was trying to install snort and everytime I encounter a problem I tried to follow this link http://www.snort.org/assets/167/IDS_deb_snort_howto.pdf but then I realized that it cannot be applied on ARM architecture !
There's a Raspberry Pi security tutorial based on ArchLinux, that includes step 13 "Snort installation".
Basically all you have to do is:
$ sudo pacman -S snort
Please, follow the instruction as close as you can.
@lenik's answer would be correct, if not for the AUR repository to not have an ARMv6 build available for snort, which is what we need for the raspberry pi. This topic describes how to build the needed package yourself with the source tarball from the AUR repository: http://www.raspberrypi.org/forums/viewtopic.php?t=36314&p=305583
Building this on the Pi will take about 1 hour, be warned :-)
I imagine the Raspbian repository has the same issue. I'm still setting up everything myself, but am wondering whether it will work reasonably in the end. Since no one seems to be making Pi-compatible ARMv6 packages for Snort, perhaps it will just be too slow to run it...
I am writing an educational Guide about Snort on Raspeberry PI, and Used two tutorials that worked fine for me:
Tut 1 Installing SNORT by (Computer and Network Security)
Using sudo aptitude install snort <---- easy way