In Windows XP, the method of obtaining the unused IP address

is used as the network administrator. When we solve the DHCP failure of the Windows operating system, we sometimes find out which addresses in an address range are not used. I have previously introduced a method: open a command prompt window, call the ping command in the For...in...Do loop. For example, to find out which addresses are not used in the address range 192.168.1.1 to 192.168.1.100, you can use this command: For /L %f in (1,1,100) Do Ping.exe -n 2 192.168.1.% f
This command reports all IP addresses in the specified range. Whether it is used or not, the user has to look through a large amount of content in the command line window. In fact, we can avoid these troubles, just create a batch file, ask it to return only those unused IP addresses, and then enter the results of the command into a text file. Here's how to do it:
Open Notepad and type the following command in the window:
@Echo offdate /t > IPList.txttime /t >> IPList.txtecho ========= == >> IPList.txtFor /L %%f in (1,1,100) Do Ping.exe -n 2 192.168.1.%%f |  Find"Request timed out." && echo 192.168.1.%%f Timed Out >>IPList.txt && echo offclsEcho Finished!@Echo onNotepad.exe IPList.txt
Save as IPTracker.bat and close the Notepad program.
It should be noted that in this batch file, the entire For...In...Do command consists of several commands connected by "&&". The command starts with "For" and ends with "Off", and the entire command must be on one line. Of course, if the user wants to use this method, the user's own IP address needs to be used to replace the IP address in the example.
Later, if the user wants to solve the DHCP problem, you can locate and double-click the IPTracker.bat file in the browser window, and then start an IP address tracking tool. This batch only finds those unused IP addresses and saves the result. Go to the notepad file. (In this case, this saved batch file becomes an IP address tracking tool that can be created once and used repeatedly.)
Note: This method is only available for Windows XP Professional