debian
Auth.log in Debian Systems
Feb 2nd
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Your auth.log file is the first step in determining of an intrusion is being attempted, or has occured. It logs all ssh connection attempts, cron jobs, and su calls. If an ssh brute force attach is occurring you will see countless failed ssh login attempts. Most likely various usernames will be attempted. You should immediately stop the ssh server and implement some security countermeasures. Implement various rules in your hosts.allow and hosts.deny files any if you want implement some iptables rules. Host.allow and deny should be enough; the files control tcp connections to your running system daemons. Iptables will block ip numbers just at the connection attempt is made to the computer so for ultimate security implemente iptables and various host rules.
After locking down your servers you will see brute force attacks stop, and your auth.log file will be mainly filled with cron jobs and su commands by users and daemons. The cron jobs are automated process run by various applications, and are mostly run as root. Mail servers, and other tasks are typically managed by cron jobs. You can check user specific cron jobs using the crontab command. Use option -e to edit a users jobs.
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Thermaltake 2U Drive Bay Cooler – System Tweaking
Jan 9th
This is my first experience with a water cooling system, and its a winner. A leak is the only thing that will make me hate water cooling, but otherwise my system is cooler than ever; pun intended. I operate at 21 – 30 C without overclocking, and overclocked to 2.6 Ghz I’m at around 35 C. Using the newely updated, and incredibly stable Debian Lenny performance is better than ever. With preload installed and a strategically implemented ram disk system performance is surely maxed out with the processor operating at such cool temperatures.
Debian Etch Compiz – Beryl
Sep 14th
Although the Debian repos have Compiz available, I have had bad experiences with what should be a routine installation. Although I have had good experiences utilizing the now outdated Beryl repos and software. To install Beryl for Debian Etch AMD64 add the following repos to your apt sources file: deb http://debian.beryl-project.org/ etch main deb-src http://debian.beryl-project.org/ etch main Add the gpg key: wget -O - http://debian.beryl-project.org/root@lupine.me.uk.gpg | sudo apt-key add - Install Beryl: sudo apt-get update && sudo apt-get install beryl-manager emerald-themes Update xorg.conf (sudo nano /etc/X11/xorg.conf): then added these two lines under the “Screen†section Option “XAANoOffscreenPixmaps†Option “AddARGBGLXVisuals†“true†then added these lines under “Device†Option “AllowGLXWithComposite†“true†Option “RenderAccel†“true†added one line under “Server Layout†Option “AIGLX†“on†Finally at the end of the file add these lines Section “Extensions†Option “Composite†“Enable†EndSection
Nagios Virtual Server Monitoring in 15 Minutes – Intro
Feb 26th
Nagios allows you to graphically monitor your virtual servers from a single web page. No longer will you have to load each individual website or web service in order to verify consistent operation. Nagios can be downloaded directly from their website at: http://www.nagios.com On the Nagios homepage is a link to a 15 minute tutorial, which is relatively straight forward, and works like a charm. I recommend Ubuntu JeOS for your virtual OS specifically because the kernel works flawlessly with the host operating system.
Debian VirtualBox Guest OS Causes High and Constant Host CPU Load
Feb 23rd
For the longest time I was using Debian for my guest operating system, and was relatively frustrated that the host OS always had a constant CPU load of over 20%. I tried many times to compile a custom kernel to resolve this issue, and in the end I decided to switch to a new OS. At first I though Ubuntu server edition was the way to go, but when I was installing the system there was all these gnome, and other graphical components being installed. What is the purpose of openoffice files in a terminal based OS? Overall Ubuntu JeOS is the way to go! It will only install the base Ubuntu system, comparable to how Debian can be configure during the installation process. The kernel used in JeOS does not cause the host to have a constant CPU load, therefore I am overwhelmingly satisfied with its performance. If you are experiencing high host CPU load with your guest OS, I recommend experimenting with different kernels, and possible switching to a different OS if you cannot resolve the issue. There is no reason your host CPU load should be high when the guest is not processing any data. JeOS is the way to go 
