I've been looking into an issue related to an ASP.NET MVC application hosted on a Windows server.
The content delivery servers auto-scaled several times a few days back.
In the application logs, I see several null reference exceptions and API call failure responses. However, those are the known errors that used to happen in the past as well.
Upon checking the AppDynamics controller, I see several event logs saying "App Server Restart", and some of these time matches with the auto-scaling events.
However, I saw the same App Server restart logs in App Dynamics today as well, but the auto-scaling didn't happen today.
I'm told that the autoscaling is configured to happen if the health check fails or if the CPU utilization is high.
I was wondering what I should look into to find out what exactly caused the auto-scaling events. Does App Server Restart cause to auto scale?
I'm curious to find out what would cause a spike in CPU utilization and health check failures.
I'm very new to the application monitoring so any suggestions or tips would be really helpful.
Thank you!