Friday, February 18, 2011

Free Wi-Fi Analysis Tools

I'm putting in a Wi-Fi network for a clieent in a couple of weeks and need to a good way to find out whether we are placing the access points properly. So, being the somewhat cheap guy that I am, I've gone looking for free tools and found a couple of good ones:
The first one I looked as was inSSIDer. This is a nice survey tool that shows you all of of the wireless networks that it sees, the signal strength, and what channel each is on. I like this one for getting an idea of what is currently on a site. This one is open source, and can hook into a serial port based GPS. An advanced paid version can also look for sources of interference.

Heat Mapper is a site mapping tool that you can use to identify signal strength at various locations in your organization. First, you import a graphic with your floor plan. Then you wander around with your laptop running Heat Mapper and click on the map corresponding to where you are. When you are done, it generates a map that shows signal strength in different areas on the map. It is displays much like a topographical map. There are more advanced paid versions of this product, but this one does a nice job for free.

I'm going to be keeping both of these tools on my laptop.

Wednesday, February 9, 2011

Cheap Exchange 2010 Storage

I continually run into resistance when discussing the idea of ditching the SAN and using direct attached storage (DAS) for Exchange 2010 implementations. There are a number of reasons that are thrown out there ranging from reliability to managability. However, in my opinion, in most cases, all of those issues can be overcome. At the very least you owe it to yourself and your organization to consider the possibility of saving some large $$ by implemementing multiple data copies in a database availability group (DAG) with DAS rather than using an expensive SAN.

This is one of the best posts I've seen regarding storage for Exchange 2010:

Monday, February 7, 2011

Using Network Monitor Captures in Wireshark

I'm a big fan of packet sniffing for troubleshooting. Just today I was trying to resolve a problem with a SharePoint site behaving inconsistently. Sometimes and only for some computers, the site would not open. After putting a packet sniffer on it, it appears to be a network problem as there are a lot of packets being resent and a lot of duplicate ACKs.

My two favorite programs for packet sniffing are both free:
  • Wireshark (open source)
  • Network Monitor (Microsoft)
Both of these packet sniffers are good, but each has difference strengths.

I was pleasantly surprised today to find out that if you save a capture in Network Monitor, that you can open it in Wireshark. This gives the ability to look at the same data in both tools. Sometimes the way one tool interprets or displays the data is easier to understand when you are looking at something specific.