I was recently stepping into a new network environment. I had inherited it with a client, had little documentation, and needed to understand it in order to be able to support it. I investigated the physical components – the switches, the firewall, the patch ports – and the software configurations – static IP addresses in illogical ranges – but was still looking for more to help prepare me for any traps or gotchas.
Using SoftPerfect Network Scanner, a freeware portable app that easily runs from a flash drive, it can scan an IP range. It pings computers to find live connections and returns Host names, MAC addresses, response times, and shared folders. It can be configured to do more and fit your environment better. The length of time it takes the scan to complete depends on how large of a range you choose and items found on the network. I have found it to be a pretty quick process for all that it does and the amount of time and pain it saves.
You can export the results to HTML, XML, CSV, or TXT formats. I used the CSV format to bring the data into Excel for further clean up and tweaking as I prepare to rearrange the network and implement a DHCP environment.
NetScan is a very handy, free tool to have available. You can download it and find the user manual at http://www.softperfect.com/products/networkscanner/