Category Archives: Computers

Simple iptables firewall script with NAT and SFQ sceduling

I have been working with firewalls and security for quite many years at this point. Therefore friends and people I know ask me every now and then to write a firewall script for them. So instead of basically writing the same script over and over again I decided to write this article that explains how you can set up a basic iptables box by yourself.

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A solution to Potential DNS DDoS: named query (cache) ‘./NS/IN’ denied

During the last couple of weeks i have been seeing a lot of messages about denied cache queries on my DNS servers.

month day time server name named[6518]: client ip number#port number: query (cache) ‘./NS/IN’ denied

At first they looked quite innocent and I thought nothing much of them. But after a while the number of logged events grew faster and faster so it was time to do some investigation on google. After reading a few articles I came to the conclusion that my logs where trying to tell me that my DNS server where used as DNS DDoS deflectors.

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A simple Mac OS X maintenance shell script

I, like so many of my fellow Macintosh users want to keep my OS X installation well maintained. So i sat down and read a few man pages describing those nifty cli utilities that are included in OS X. Since OS X is a UNIX style operating system I decided to create a small shell script to perform the following maintenance tasks for me .

Repair Filesystem Permissions
Verify Disks
Run Periodic (cron) jobs
Update Prebindings
Verify Preference Files
Displa Cache size
Clear Cache

If you find the script interesting and want to use it on your mac you need to perform a few simple steps:

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