Application Insights: Filter website health checks?

Question

I'm using Azure Application Insights on the free tier. We also use amazon AWS health checks that hits a pre-determined page expecting a 200 response it then does things if it gets a different response.

All the requests from AWS are filling up telemetry pretty quickly.

Is there a simple way to filter or exclude these requests?

Can it be done from the App Insights console, or does it require modifying the telemetry collector on the actual application. I'd rather not create my own implementation of the ITelemtryProcessor...

And if i am stuck going that route, would this work to filter AWS Route53 checks?

public void Process(ITelemetry item)
{
  if (!string.IsNullOrEmpty(item.Context.Operation.SyntheticSource)) {return;}
  this.Next.Process(item);
}

Edit-Update

Has anyone seen this part of the applicationinsights.config I'm not certain by what it means that it will not have correlation headers.

 <ExcludeComponentCorrelationHttpHeadersOnDomains>
    <!-- 
    Requests to the following hostnames will not be modified by adding correlation headers. 
    This is only applicable if Profiler is installed via either StatusMonitor or Azure Extension.
    Add entries here to exclude additional hostnames.
    NOTE: this configuration will be lost upon NuGet upgrade.
    -->
    <Add>core.windows.net</Add>
    <Add>core.chinacloudapi.cn</Add>
    <Add>core.cloudapi.de</Add>
    <Add>core.usgovcloudapi.net</Add>
    <Add>localhost</Add>
    <Add>127.0.0.1</Add>
  </ExcludeComponentCorrelationHttpHeadersOnDomains>

Does anyone have any other resources or tutorials, the only one i was able to find: https://docs.microsoft.com/en-us/azure/application-insights/app-insights-api-filtering-sampling#filtering

It seems that probably most simple way to implement is to grab a collection from the web.config, define the processor in its own class file, then insert the processor into the chain into the global config...

John Gardner John Gardner · Accepted Answer · 2017-09-13T18:22:23

You'll have to write a telemetry initializer like you have above.

However, you might want to look more specifically at the synthetic source and verify content and only throw away the amazon health checks instead of all synthetic traffic (you could also look at request name, etc to make your decisions), as i'm not exactly sure what information is in those inbound requests from amazon.

Otherwise, you might be throwing away incoming requests/dependencies/exceptions that might occur from your webtests, which would also show up as synthetic.

Application Insights: Filter website health checks?

1 Answers