Taiob Ali looks at the system_health Extended Events session:
What this article does not tell you is your individual file size is 5 MB and number of maximum rollover file is 4. Meaning you will only get 20 MB of data. Once that limit is reached your older data is lost and there is no way to recover.
Often time you have an issue with the application pointing to SQL Server and you want to diagnose the problem with system_health files. You find that files already rolled over and information you are looking for is not available. I will explain how you can solve this problem and retain system_health session files for longer period.
Read on for the solution.