Application Insights - Faulted Error code from Dependencies in Az blob storage

Question

We are using Az blob storage, and it's reached few time maximum threshold. Due to this getting DNS error code in dependencies, but dependency collector updating as Faulted. How can we avoid this Faulted error code.

Please check marked error code and share your thoughts.

Answer 1

• The ‘faulted’ error code that you are encountering in the ‘Application Insights’ top response codes is related to the ‘DependencyCollection’ module tracking an Exception event along with a ‘DependencyTelemetry’ in the event of client-side errors like DNS. Since you are also getting DNS error code in dependencies related to Azure blob storage reaching maximum threshold, it is a common error code related to above said scenario irrespective of whether the Azure resource is a blob storage or an APIM.

• Thus, this error code is an exception which is sent to user ‘ikey’ along with Dependency Telemetry. So, if this exception is not tracked, then the only information ‘DependencyCollector’ has is that the call failed, and ‘resultCode’ is reported as "Faulted". As a result, you should modify the result code to be more useful, before removing the actual exception.

For more detailed information regarding this ‘faulted’ error code, please refer to the below SO community thread and its comments discussions as well as also into the github community discussion forum link given below. They discuss the probable cause of this error to be the timeout for ‘GET’ request resulting in thread starvation or poor application performance or might be a lot of context switching resulting in a high threadpool count.

Azure AppInsights - Http Result code Faulted

https://github.com/microsoft/ApplicationInsights-dotnet/issues/1362#issuecomment-511488536