I need to build a script that checks a log file on the IIS and parses how many 'HTTP Status = 503' strings are found. If it founds one, an alert is triggered.
Lots of ways to do this, there's a built in Log Parser for Powershell application template:
There are custom options:
There are other ways to get similar results by using HTTP/HTTPS monitors and Windows Event Log monitors if the information is found there as well, but I wanted to answer your question more along the ways it was asked.
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