Kubernetes notes
Collection of my different Kubernetes notes mostly in context of Azure Kubernetes Service (AKS) or Azure Arc-enabled Kubernetes but also some that are also relevant for vanilla Kubernetes.
Super important topics to understand
- Understand the Kubernetes release cycle
- ~3 releases per year
- 3 minor versions supported at a time
- Support window is one year
- Understand Azure Kubernetes Service (AKS) Kubernetes Release Calendar
All of the above just means that
There is no such thing as Kubernetes Long-term support (LTS)*
and
Due to frequent releases you need to upgrade at least once per year
and
You need to plan your cluster upgrades
because many things might break because of Kubernetes API deprecations.
*: Microsoft has added LTS support for AKS clusters. Read more from Long Term Support (LTS).
Playgrounds
Different playgrounds have been created for testing very specific scenario.
They also contain simple deployment script either written in
bash or PowerShell which you can run line by line
and replicate that environment for your own testing purposes.
Storage
Monitoring
Identity
Maintenance
Windows
Networking
Playground for AKS and AGIC (Application Gateway Ingress Controller)
Development
Multi-tenancy
Repository contains discussion topics around multi-tenancy options.
Azure Red Hat OpenShift (ARO)
Playground for Azure Red Hat OpenShift (ARO)
Azure Arc
Misc
kubernetes webhook controller in C#
End-to-end scenarios
Tools
Check tools page for more information about handy tools for your automation scenarios.
Discussion topics
- Development process
- Automation
- Add-ons, extensions, and other integrations with Azure Kubernetes Service
Add-ons are a fully supported way to provide extra capabilities for your AKS cluster. Add-ons' installation, configuration, and lifecycle is managed by AKS.
- Support and Who ya gonna call?
- In-cluster vs. out-of-cluster components
- Database or messaging service from PaaS or DIY
- Support to handle support for DIY!
- GitOps vs. Traditional CI/CD a.k.a.
kubectl apply ... - Multi-tenancy
- Cluster management
- RACI
- Operational tasks
- Monitoring
- Cluster upgrades
- Application manifest updates
- You need to understand Kubernetes specific details -> Certified Kubernetes Administrator (CKA) required?
- Monitoring
- App vs. Cluster monitoring
- Innerloop development & microservice debugging