Container Orchestration - Kubernetes and OpenShift

Running Docker Containers in production brings several challenges. Container orchestration tools and platforms provide solutions for them. We will look at Kubernetes - the leader in container orchestration - to understand the concepts and how to deploy applications. OpenShift adds additional features to Kubernetes, which makes it a full PaaS solution for the enterprise.

Transcript

1. Christian Köberl
   Container Orchestration
   

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2. Christian Köberl
   Software Architect / Developer
   Develops web apps since 1999
   

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3. Linux Containers
   Source: https://www.redhat.com/de/containers/whats-a-linux-container
   

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4. Docker
   Source: https://docs.docker.com/opensource/ways/meetups/
   

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5. Simple Deployment
   SSH into machine – docker run myapp
   • Very simple
   • BUT what about
   • Failure – who/what restarts the container?
   • Load Balancing
   • Scaling
   • Updates
   • …
   

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7. Source: http://www.cargolaw.com/2011nightmare_mv_rena.html
   

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8. Why Container Orchestration?
   • High Availability
   • Running on multiple hosts
   • (Auto-)Scaling
   • Load Balancing
   • Rolling Upgrades
   • Storage management
   • Monitoring
   • Authentication & Authorization
   

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9. Scheduler
   Container Orchestration
   Scheduler
   Node 1 Node 2 Node 3
   Run 3 instances of
   MyApp
   Distributed Database
   Container Engine Container Engine Container Engine
   Run Postgres where
   backup=yes
   backup=yes
   Postgres
   MyApp
   MyApp MyApp
   

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10. Network
    Container Orchestration
    Node 1 Node 2 Node 3
    Container Engine Container Engine Container Engine
    Postgres
    MyApp
    MyApp
    MyApp
    172.16.0.2 172.16.0.3
    192.168.0.12
    10.40.1.12
    10.40.1.13 10.40.1.14
    

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11. Service Discovery / Load Balancing
    Container Orchestration
    Node 1 Node 2 Node 3
    Container Engine Container Engine Container Engine
    Postgres
    MyApp
    MyApp
    MyApp
    myapp:80
    myapp:80 myapp:80
    (External)
    Load Balancer
    myapp.domain.com
    

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12. Container Orchestration - Additional Features
    • Resource Management
    • CPU (GPU) / Memory
    • (Persistent) Volumes
    • Configuration / Secret Management
    • Distributed Job Scheduling (CRON)
    • Container Registry
    • …
    

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13. With good Container Orchestration
    your whole data center will look like a
    single server with endless resources.
    > Data center operating system
    https://www.oreilly.com/ideas/why-the-data-center-needs-an-operating-system
    

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14. Competing Systems
    Kubernetes Mesos Docker Datacenter
    

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15. Production-Grade Container Orchestration
    

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17. Abhishek Verma, Luis Pedrosa, Madhukar R. Korupolu, David Oppenheimer, Eric Tune, John Wilkes:
    Large-scale cluster management at Google with Borg, https://research.google.com/pubs/pub43438.html
    Google's
    BORG
    Kuberntes Master
    Kubelet
    Kubelet
    Kubelet
    Kubelet
    etcd
    Kubernetes
    YAML/JSON
    

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18. Demo 1 - Wekan
    • Deploying Wekan
    1. Deploy MongoDB with Volume
    2. Deploy Wekan application
    

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19. K8s – Logical View
    Namespace
    Service
    Pod
    Container
    Container
    Pod
    Container
    Container
    ReplicaSet
    Deployment
    Pod
    Container
    Volume
    ReplicaSet
    Deployment
    Service
    Secret
    ConfigMap
    

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20. Kubernetes - Concepts
    • Workloads
    • Pod
    • Deployment
    • ReplicaSet (former Replication Controller)
    • StatefulSet – for legacy apps
    • Job / CronJob
    • Service
    • Volume
    • Configuration
    • ConfigMap
    • Secret
    

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21. Kubernetes - Objects + REST API
    • All objects represented in YAML or JSON
    • REST API for all objects
    • Command Line and UI talk to REST API
    

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22. Service apiVersion: v1
    kind: Service
    metadata:
    labels:
    app: wekandb
    version: "3.4"
    name: wekandb
    namespace: wekan
    spec:
    ports:
    - name: tcp-27017
    port: 27017
    protocol: TCP
    targetPort: 27017
    selector:
    app: wekandb
    version: "3.4"
    sessionAffinity: None
    type: ClusterIP
    

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23. Red Hat® OpenShift is a container application platform
    that brings Docker and Kubernetes to the enterprise.
    

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24. Demo 2 - Angular Heroes
    • Deploy Angular Spring Heroes
    • Angular Heroes Tutorial App
    • Spring Boot Backend
    • https://github.com/porscheinformatik/angular-spring-heroes
    • Update Code
    • GitHub Webhook triggers build
    

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25. OpenShift – Kubernetes PaaS
    • ImageStreams
    • Automatically Update Images / Deployments
    • Builds / Pipelines
    • Build from Source/Binary
    • Build via S2I or Docker (or custom)
    • Jenkins Pipeline Integration
    • Routes – integrated LB (HAProxy)
    • Templates
    • Blueprint for whole application
    

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26. OpenShift – Enterprise Kubernetes
    • SELinux with RHEL, CentOS or Atomic
    • Container running as non-root
    • Network Isolation between Namespaces
    • Automatic Security Updates via ImageStream/Builds
    

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27. https://learn.openshift.com
    

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28. Local Environment
    • Kubernetes - minikube
    • minikube start
    • Starts k8s cluster in VM
    • OpenShift
    • minishift
    same as minikube
    • oc cluster up
    Runs cluster in Docker containers
    

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29. Kubernetes Ecosystem
    • Lot's of cloud providers, biggest include Google, IBM, Microsoft
    • Different PaaS solutions: Deis, OpenShift, Kel, …
    • Helm
    • Kubernetes package manager
    • Installs whole application + dependencies
    

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30. Thanks! Questions?
    github.com/derkoe / @derkoe
    Source: https://www.docker.com/community-edition
    

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