a little mans look at a big mans world

Sometimes we need to see if a computer is making the connections that we think it should be making. For those situations, netstat is there for us. There are any number of reasons why we would want to diagnose a connection. To ensure that a client is talking to a server, that is one big reason that I can see. In another case, if I have access, I like looking at a machine that I am scanning with nmap or some other tool when I am scanning it, it can be informative to see those connections pop open. If I was using netstat on a Linux machine then my command would probably look something like this:

sudo netstat -na -c | grep "192.168.0.2"

You would run this example on the computer that you were scanning. The IP address is the address of the host that you are scanning from, or the client that you want to make sure is connecting to the server. So what have you done here? First, you ran netstat, with a few options that provide detailed output, and tell it to run in a loop, checking for connections continuously. Read more

Nmap is one of my favorite tools. Ostensibly, it is only a simple port scanner, but it can be used as one of the best discovery tools there is. It does require some command line proficiency. One thing that comes up often is this case. I am looking at an IP block, and I want to know which hosts are up and running. Knowing which machines are running can significantly lower your scan space, thus saving you time. Scanning an IP block with default settings is certainly doable, but pretty wasteful. Here is the command you could use to do that:

nmap 192.168.0.0/24

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I love network security, firewalls in particular. I have done some pretty extensive fire-walling with OpenBSD and I learned a ton along the way. I tried to write down what I learned, and have gone back to reference the resulting document multiple times when doing installs or upgrades. So I wanted to post up on my blog some of that in a how-to format. This guide will take you through the installation and initial configuration of an OpenBSD firewall, which, depending on the hardware, could be suitable for home or office use.

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One of the things I like about Wordpress is it’s ultra simple methods of updating blogs. This little post was tapped out without to much trouble on my iPhone, which, when you think about it, is an amazing accomplishment. It is trivially simple to set this up, especially after setting up the rest of the blogs server. If I didn’t actually do the work to setup my own server, I cannot imagine how simple it would be to get up and going with a blog. Truly, the barriers to successful blogging have been effectively reduced to one, having something worthwhile to say. Now to decide what I really want to say.

I have once again changed my homepage in my never ending quest to realize some unknown quantity. I have switched my CMS yet again, mostly because I have no need for the power of Drupal, and for the most part I do not have the expertise needed to make Drupal what I wanted. Fantastic CMS, though, if I wanted a framework, I know where I would look, but since I prefer to have something with more meat attached, I have switched to WordPress, for its simplicity and wonderful free plugins, etc. Regardless, I am building towards perfection, so expect more changes.