Cranking out news for the geeks, music buffs and gossip junkies, my way. -Greg

Iptables in the simplest explanation is a firewall. It’s actually a program that allows the administrator to configure a set of rules that allow or deny traffic in and out of the machine it’s running on. I’m sure most anyone that has some basic understanding of their Linksys or NETGEAR routers can understand the firewall that is built into those devices. Maybe you setup RDP (remote desktop protocol) on 1 of you PC’s and had to open port 3389 and forward that to the IP address of your desktop. This is a firewall function, it’s allowing traffic to enter your network on port 3389 to a specific destination, in this case you desktop. Well Iptables is both complex in its endless ability to be very specific to the rules you set forth and simple (once you understand it) in the fact that there is no guess work, 1+1 will give you 2. nixCraft has written and excellent article on Iptables “Linux: 20 Iptables Examples For New SysAdmins“. The article makes understanding Iptables pretty easy for everyone as long as you have a basic understanding of network routing and firewalls. nixCraft has been one of the greatest resources (next asking a Linux / UNIX guru) I’ve found for help with do pretty much anything with Linux or UNIX. They have really done a great job of explaining Iptables by definition and examples. Head over to nixCraft and soak up Iptables knowledge today. –Greg

Ever replace a production firewall with a new or different technology or platform? I have, and going from ipfw to iptables, or going from a TechGuard to Cisco ASA is not the easiest. Although I can appreciate doing it by tearing down each line and understanding it before rebuilding into a new platform, things would have been a lot easier had I had the use of Firewall Builder 4.0. This nifty tool allows you to user their GUI and build you firewall set and then export to the firewall platform of your choice. It can also act as a firewall translator if you will, as you can change from 1 platform to another.

You can generate configuration for a range of devices starting from small Linksys, D-Link and other routers running DD-WRT or OpenWRT, to firewalls running Linux, FreeBSD or OpenBSD on a regular or purpose-built PC, to Cisco routers and Cisco ASA (PIX) firewalls.

Firewall Builder 4.0 allows you a free 30 day evaluation and a license will set you back about $79. It’s available on Linux, Windows, and even Mac. Firewall Builder 4.0 is still in beta, but I expect this will be a great tool for any admin or engineers thumb drive. If anyone knows of anything similar or better I would love to know about it. -Greg

Google launched their own public DNS service yesterday. In an effort to (take over the world) speed up DNS resolution, Google created their own DNS servers for the public. I honestly had never thought much about DNS being a bottle neck for surfing the web. Today I swapped out my Open-DNS servers for Google’s DNS servers and punched up a few different sites. I did site that I have been too as well as sites I haven’t been too, I’d have to say they are loading (resolving) noticeably faster! So, maybe DNS resolution could be a real bottle neck, that personally had never crossed my mind. Google could potentially take over the world, if only by offering better services in everything. Good show Google, good show! -Greg

Here are Google’s public DNS servers:

• 8.8.8.8
• 8.8.4.4

and for those of you who may need a little more info on what the heck I’m talking about or how to put Google’s public DNS in to use on your Windows, Mac, or Linux (if your using UNIX, I’m pretty sure you know what the heck your doing) machines, point your browsers too:

Using Google Public DNS

So it looks like Google is about to release its Chrome OS sometime this week. I’m curious how it will stand up to Ubuntu, which is obviously the most popular and average user friendly. I will be loading it up on a VM and play with it, but I’m not even thinking about the possibility of replacing my main OS, Win 7. Linux is great, but Windows will always be my primary OS. -Greg