Below are the information that you can get from IIS Server to see your server availability. Health of the IIS Server depends upon the health of the websites. Health of the Website depends upon attributes that are mentioned below:
Bytes Transferred : Bytes Sent Per Second, Bytes Received per Second, Bytes Total Per Second
Files Transferred: Files Sent Per sec, Files Received Per sec, Files Transferred Per Sec
Connection Statistics: Current Connections
Anonymous Users: Current Annonymous Users, Anonymous Users per Second
Non Anonymous Users: Current NonAnonymous Users, Non Anonymous Users per Second
so from now use your log parser tool to see how health your server
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