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dotnet monitor–Run as a sidecar in a Kubernetes cluster–Part 2

Last week I blogged about how you can run dotnet monitor as a sidecar in your Kubernetes cluster. Although the yaml file I shared worked on my local cluster (inside Minikube), it didn’t work when I tried to deploy it to AKS. Nothing happened when I tried to connect to the specified URL’s.

To fix this I had to take multiple steps:

  • First I had to explicitly set the ‘—urls’ argument inside the manifest:
  • Now I was able to connect to the url but it still failed. When I took a look at the logs I noticed the following message:

{"Timestamp":"2021-07-27T18:48:29.6522095Z","EventId":7,"LogLevel":"Information","Category":"Microsoft.Diagnostics.Tools.Monitor.ApiKeyAuthenticationHandler","Message":"MonitorApiKey was not authenticated. Failure message: API key authentication not configured.","State":{"Message":"MonitorApiKey was not authenticated. Failure message: API key authentication not configured.","AuthenticationScheme":"MonitorApiKey","FailureMessage":"API key authentication not configured.","{OriginalFormat}":"{AuthenticationScheme} was not authenticated. Failure message: {FailureMessage}"},"Scopes":[{"Message":"ConnectionId:0HMAH5RL3D6BM","ConnectionId":"0HMAH5RL3D6BM"},{"Message":"RequestPath:/processes RequestId:0HMAH5RL3D6BM:00000001, SpanId:|fe3ec0c2-46980a5b9b2602e2., TraceId:fe3ec0c2-46980a5b9b2602e2, ParentId:","RequestId":"0HMAH5RL3D6BM:00000001","RequestPath":"/processes","SpanId":"|fe3ec0c2-46980a5b9b2602e2.","TraceId":"fe3ec0c2-46980a5b9b2602e2","ParentId":""}]}

  • We need to create an API key secret and mount it as a volume to our sidecar. Here is the code to generate a secret:
kubectl create secret generic apikey \
  --from-literal=ApiAuthentication__ApiKeyHash=$hash \
  --from-literal=ApiAuthentication__ApiKeyHashType=SHA256 \
  --dry-run=client -o yaml \
  | kubectl apply -f -
  • Now we need to mount the secret as a volume. Here is the updated manifest:

If you want to learn more, I could recommend the following video as a good introduction:

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