HTTP Request processing in IIS

0
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To understand how IIS processes a request, I have used the diagram here: https://blogs.iis.net/tomwoolums/iis-7-0-http-request-processing

My questions:

  • Is step 1 until 5 executed for every request or only for the very first request?
  • Who is actually sending the request to the application pool? WAS? Or does WAS only create/map the worker process for the request and HTTP.sys sends the actual request to the worker process? If WAS sends the actual request, why would we need to configure the HTTP.sys if the request is passed to WAS, which already knows the configuration?
  • Am I right if I say: The application pool passes the response directly to the HTTP.sys?
1
iishttprequest

1 Answers

1
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  • Step 1-5 is generally speaking executed once for multiple requests. When you change certain settings in IIS configuration, then a new request will trigger step 1-5 again.
  • Requests only go through http.sys and worker processes. WAS only manages worker process lifecycle, and that's why it is called Windows Process Activation Service.
  • Correct.