Refreshing iptables

The last time I played around with IPTables was about 6 - 7 years back. I have been working with a Linux box again from the last few months and I am absolutely thrilled about it. Nevertheless, I have also been meaning to set up a simple IPTables firewall on my machine.

Since I had forgotten all my IPTables concepts, I decided to hunt the Internet for some good articles. I found some really nice resources to refresh my memory as well as learn new things.

Here is a nice 3 part video series from Linux Journal.

The entire series takes less than a half hour and is a good refresher or introduction to IPTables.

Here is a nice picture which explains how a packet is routed through various chains in the ip tables. If you are looking for a quick refresher, this might help you out.

If you want more details, here is a tutorial, and yet another tutorial, and Netfilter's excellent documentation on IPTables.

So now there is no excuse for not setting up a little firewall on your Linux box.

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