AKS Learn feedback: Cost analysis requirement of Prometheus not documented

[mloskot]

Type of issue

Missing information

Feedback

The AKS cost analysis feature, AFAIU, is based on OpenCost. The OpenCost requirements state clearly the Prometheus is required.

This requirement is not mentioned in the AKS cost analysis prerequisites or anywhere in the AKS cost analysis documentation, neither that it requires Azure-managed Prometheus or self-managed Prometheus deployment.

I have enabled the AKS cost analysis to one of AKS clusters which has no Prometheus enabled or deployed and

• Azure Portal > my cluster > Cost analysis displays "No cost data to show"
• kube-system/cost-analysis-agent-xxx has been deployed >24h ago
• kube-system/cost-analysis-agent-xxx logs stream lots of warnings like

  WRN node pool name not supported for this provider
  WRN ETL: did not find allocations for asset key
  WRN Failed to load 'id' field for ClusterInfo
  

Presumably, due to lack of the Prometheus, but how a user should know?

(For the records, I've also asked about it in thread on #azure-aks at kubernetes.slack.com and thread on #opencost at cloud-native.slack.com, but without any response so far.)

Page URL

https://learn.microsoft.com/en-us/azure/aks/cost-analysis#prerequisites

Content source URL

https://github.com/MicrosoftDocs/azure-aks-docs/blob/main/articles/aks/cost-analysis.md

Author

@schaffererin

Document Id

51555159-2b0c-85a4-9524-090f4f4553cd

Platform Id

af3b4b37-7d4b-f678-16f0-89c3b38d2f6e

[mloskot]

On #opencost channel at cloud-native.slack.com I received answer that Prometheus is not required because, quoting:

A victoria metrics container runs inside cost-analysis-agent pod.

I still think a word of clarification in the Azure documentation would be useful to users.