How can I locate unused IP addresses on my network? The DHCP server keeps assigning the same address and I need a different IP address to test my application with. The software would need to run on Windows.
How to Find Unused IP Addresses on a Windows Network
dhcpipnetworkingwindows
Related Solutions
One simple method is to simply run a sniffer like tcpdump/wireshark on a computer and send out a DHCP request. If you see any offers other then from your real DHCP server then you know you have a problem.
Best Answer
Probably the best way is to use NMAP (http://nmap.org/) in ARP Ping scan mode. The usage will be something like
nmap -sP -PR 192.168.0.*(or whatever your network is).The advantage of this approach is that it uses the Address Resolution Protocol to detect if IP addresses are assigned to machines. Any machine that wants to be found on a network needs to answer the ARP, so this approach works where ping scans, broadcast pings and port scans don't (due to firewalls, OS policy, etc.).