KEDA - Mastering Scale to Zero by Daniel Hasselwander

Slides from the following meetup: https://www.meetup.com/de-DE/microsoft-azure-zurich-user-group/events/292938328/

KEDA is an Event Driven Autoscaler for workloads running on Kubernetes. It provides mechanisms to scale those workloads depending on external systems, such as messaging or telemetry systems.

This talk will provide an introduction to KEDA and the underlying concepts. The usage of KEDA will be demonstrated on Azure with an AKS cluster running a demo application, which is autoscaled through KEDA. We will see how to setup KEDA and configure it to scale the application depending on the amount of messages in an Azure Service Bus Topic

About Daniel:
I have been working as an Azure Engineer at ti&m in Zurich since 2021. Ti&m is an IT service provider offering services along the entire IT value chain. My role is to support customers in the selection of Azure Cloud components and to implement them afterwards. My main technologies are container technologies (e.g. AKS) and Terraform as an IaaC tool.

https://www.linkedin.com/in/daniel-ha%C3%9Felwander-786826137/

Transcript

1. Keda
   Mastering Scale-to-Zero
   Daniel Hasselwander
   Zürich, 16.05.2023
   Azure Zürich User Group
   

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3. It is Monday 10AM, now
   Some person leaves the house and goes to work
   

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5. Why is this situation important for today
   

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6. What is a good software ?
   

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7. Doing the right things, with as little cost
   in operations as possible
   

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8. Same Picture – another Situation
   

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9. Node 1 Node 2 Node 3 Node 4
   

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10. It is Sunday, now
    

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11. Node 1 Node 2 Node 3 Node 4
    

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12. What we want
    

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13. Node 1 Node 2
    

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14. Our Path
    What is
    Keda
    What we
    want
    How it
    works
    Demo
    

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15. Who am I ?
    

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16. Scale-To-Zero
    What we want ?
    Scale Workload
    on external
    metric
    1 0
    or
    0 1
    

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17. What is Keda ?
    − Kubernetes-based Event Driven Autoscaler
    − Works alongside standard components
    − Installable with helm
    − Doku on keda.sh
    

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18. Agent – Scale to Zero
    activate and deactivate
    Deployments
    «keda-operator» container
    How it works ? KEDA Parts
    Metrics Server
    exposes event data for HPA to
    scale out
    «keda-operator-metrics-
    apiserver» container
    

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19. ScaledObjects
    Events Deployment etc.
    How it works ? Custom Ressources (CRD)
    ScaledJobs
    Events Kubernetes Job
    TriggerAuthentication
    Namespace useable
    credentials
    ClusterTriggerAuthentication
    Cluster useable credentials
    

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20. Demo
    

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21. Demo 1
    

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22. Demo 2
    

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23. But what if my application work with http requests
    

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24. KEDA – HTTP Scaler
    − An HTTP "event" is not well defined
    − no out-of-the-box single system that can provide an API
    to measure the current number of incoming HTTP
    events or requests.
    − must to be integrated into the HTTP routing system
    

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25. KEDA – HTTP Scaler Add-On
    − KEDA core project has purposely not built generic
    HTTP-based scaling
    − Beta Status
    − Try it and give the community feedback
    − GitHub - kedacore/http-add-on: Add-on for KEDA to
    scale HTTP workloads
    

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26. Node 1 Node 2 Node 3 Node 4
    

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27. It is the next Sunday, now
    

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28. Node 1 Node 2
    

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29. KEDA – When to use it
    − Can be your default scale mechanism
    − Scale-To-Zero != Realtime
    − Azure Function in your Cluster
    

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30. KEDA – Good to know
    − Short polling only for activate deployment
    − Don´t combine ScaleObject with HPA
    − Can use multiple scaler
    − Scale on your own systems
    − Azure CLI implement a KEDA extension for Functions
    

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31. The Code is published on Github
    Hassel93/cn_meetup_keda: Repository with all used files
    for demo of (github.com)
    

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32. Thank you for your attention !
    Questions ?
    

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