There is tool IISApp.vbs in windows 2003 server which list all the application,application Pool Name and PID.
The script is already placed in systemroot\system32 on Windows Server 2003 so simply go to your Command Prompt and type in iisapp.vbs (the .vbs is optional) and you’ll have an instant list of all the App Pool information you’ve always wanted to know. You may need to type cscript iisapp.vbs if CScript isn’t your default WSH script host.
Have no worries, Microsoft has given us the exact tool for the situation. IISApp.vbs lists all the applications, their PID and their App Pool name.
Let’s see an example of the output:
W3WP.exe PID: 1468 AppPoolId: AppPoolForSite1.com
W3WP.exe PID: 3056 AppPoolId: AppPoolForSite2.com
W3WP.exe PID: 1316 AppPoolId: AppPoolForSite3.com
