Tag Archives: networking

HOWTO: disable IPv6 networking in Debian

Is IPv6 ready?

UPDATE: It’s been some time since I posted this, but I just read a post called Linux Hardening – Quick Wins that reinforces my thinking on this point; if you don’t need a service, you shouldn’t have it running:

Disable IPv6: Unless you know that you need it, disabling IPv6 is a good idea as it is hard to monitor, making it attractive for hackers, and it’s also hard to spot security vulnerabilities in the protocol.

Again, this is no shot at IPv6, merely my point that if you’re not using it, you shouldn’t be running it.

Tonight I did ran netstat (`netstat -plunt`) on my Debian server and saw that I had some ports listening via IPv6.  It’s a shame IPv6 hasn’t caught on as it’s better than IPv4 in virtually every way, and it should, especially since TCP/IPv4 was standardized in ARPANET RFC’s… in 1981!  Also, IPv6 provides network level security via IPSec, which enables authentication of sender and encryption of communication path, to secure communications, all fun stuff, but while some point to the fact that the Beijing Olympics used IPv6 exclusively as a point in how far it’s come, that’s hardly saying much when the protocol went Alpha… in 1996!  I mean I put things off and get distracted, sure, but come on!  So while its adoption can be argued to be a case of the chicken before the egg, since I’m not using anything IPv6, nor do I or my ISP even have the capability to use it, it’s silly and perhaps dangerous to leave it running with open ports.  So, if you’re not using it, disable it – it’s easy, just put on your pointy hat and follow along…

Army: Twitter could be a terrorist tool

Tweet, tweet, bomb, bomb

Tweet, tweet, bomb?

Hmmm…so the Army has claimed that terrorists may be ‘tweeting’ along to plan and organize attacks. Well yeah, I guess they could use Gmail, Slashdot comments and other things the same way, it seems their claim is that since this is more ‘real time’ it could be a danger. Ok, oh, and they take a swipe at Skype as well. Additionally they define a new name I would happily accept, “The report describes hacktivists as politically motivated hackers“. Hacktvist, that’s awesome. The report goes on with,

Distributing biodiversity data globally

My current project at work will take me far into next year, and that’s good because I’m facing an unprecedented amount of data, that will only continue to grow.  Because of this I’m finally getting to put my money where my mouth is.  For years I’ve talked about my ideas and theories about how I could network disparate systems together and have them leverage each other to keep everything in sync.  So, while working with Open Source to push boundaries I seem to find more ways to do more complex things.  One basic idea that I’m working on now is that data sets are huge, and are only going to get huger (and hugerer) as time goes on, how to handle this has been solved a few different ways.  Usually it’s someone like the Internet Archive who have 1000s of computers networked together to share the data (they are using some parts of hadoop for the distributed file system, and then nutch for search indexing) – but it’s still working from one central point of failure.  I started doing research to find out how this has been solved before, and if my idea of building a BitTorrent network was sound – and I found some great information to build on.  As I’m setting up my demo BitTorrent tracker in Debian, this info keeps me thinking of the best ways to implement my ideas.  Much of my progress is due to the very helpful advice of Paul at Geograph Torrent Archive, a project that has somewhat similar goals.

HOWTO: webserver in 100 lines of Bash

I’m a big Bash fan, I know Perl is the more popular scripting language, and I’m slowly using it more, but hey, if I need something done, I can do it quicker in Bash (keeping in mind that I’m a systems guy, not a dev guy). While at work looking up Bash related syntax I came across a page describing how to run a webserver with 100 lines of Bash. It uses the old school GNU utility Netcat (nc) for communication between the pipes, and just a ton of basic logic and functions to pass it on to the user. It’s one of those things I look at and can’t believe it works, but it does. Of course security is unknown, as is the original author, but I consider this a reference on how to do networking things in Bash; who knows what I’ll use (parts) of it for. If anyone has details on who originally wrote this I’m all ears.[sourcecode language='xml']#!/bin/bash