Intro to Kubernetes

Why Should I learn about Kubernetes and what are some basics

https://www.youtube.com/watch?v=wjOFupwbpX4&t=3444s

Transcript

1. Intro to Kubernetes
   Christopher M Luciano
   

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2. About Me
   ● Advisory Software Engineer @ IBM
   ● Part of Open Source Technology Team in IBM Digital Business Group
   ● Work on Kubernetes and other Cloud Native Computing Foundation
   (CNCF) projects
   ● @cmluciano_ on Twitter
   

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3. Index
   ● Who and Why Kubernetes
   ● Kubernetes Architecture
   ● Kubernetes Application Concepts
   ● Demo
   ● Can someone else run this for me?
   

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4. Building an Application
   My application
   

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5. Deploying
   Super_bash_script_deluxe.sh Upgrade_to_the_max.sh
   

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6. Deploying
   better_upgrader_in_python.py
   

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7. Deploying
   Better_upgrader_in_python_tests.py
   Better_upgrader_in_python_tests_with_awesomeframework.py
   

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8. Problem
   Stacks
   On
   Stacks
   On
   Stacks
   

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9. Running an Application
   start_it_up.sh
   

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10. Running an Application
    

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11. Running an Application
    

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12. Problem
    My application is a daily menu sign on a breezy day
    Sign falls down -> pick up -> return to step 1
    

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13. Scaling an Application
    Great Success!!!
    

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14. Scaling an Application
    Great Success!!!
    

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15. Scaling an Application
    More traffic,
    more power
    

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16. Scaling an Application
    Not enough traffic, need
    less servers
    

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17. Problem
    I need my organic orange juice consumption to not be affected
    by the rise and fall of traffic to my service.
    

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18. Upgrading an application
    

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19. Upgrading an application
    Display update 5 of 20
    machines
    

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20. Upgrading an application
    Oh no Video 3 is there!!!
    

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21. Upgrading an Application
    Need to add another arbitrary
    metric for “Is It Working” next
    time
    

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22. Problem
    I have a lot of avocados here but I only want the ones that will yield guacamole
    TONIGHT!!!
    

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23. Scheduling an Application
    One application to rule,
    them all
    

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24. Scheduling an Application
    

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25. Scheduling an Application
    Need to add another arbitrary
    metric for “Is It Working” yet
    again
    

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26. Problem
    I need to be sure that I can rearrange cars
    efficiently, when a large SUV needs to get to
    the Penguins game now!
    

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27. Summary of Problems
    ○ Capacity management during peak times
    ○ Scheduling for unpredictability
    ○ Reliable upgrades
    ○ Deploying the same way every time
    ○ Allow the machines to monitor and fix themselves
    

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28. Kubernetes
    Welcome to The Presentation
    

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29. Kubernetes Master Components
    ● Etcd
    ○ Backing datastore for K8s
    ○ Stores all cluster related information
    ● Kube-apiserver
    ○ From end API server for Kubernetes that exposes the Kube API to clients
    ● Kube-controller-manager
    ○ Runs Kube controllers that perform routine tasks like populating endpoints, tracking nodes that appear and leave,
    etc
    ● Kube-scheduler
    ○ Watches for new pod creations that are not running and finds a node for them to run on
    

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30. Kubernetes Node Components
    ● Kubelet
    ○ Collects all resources and detail on a given worker node and exposes them for scheduling
    ○ Also takes care of the pod lifecycle which includes mounting volumes, downloading dependencies, etc.
    ● Kube-proxy
    ○ Maintains network rules and connection forwarding
    ■ Normally done through IPtables
    ● Container Runtime
    ○ Rkt
    ○ Docker
    ● Supervisord
    ○ Babysits the kubelet as systemd would
    

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31. Core Concepts
    

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32. Container
    ● Basic building block
    ● Should contain one process or application
    ● Ex.
    https://gist.github.ibm.com/cmluciano/b52e3764b3bdcb826ae37b039d9f
    b2be
    

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33. Pod
    ● Collection of containers
    ○ Can store things in a pod specific scratch space
    ○ Can talk to each other over localhost
    ○ Scheduled to a node as a group
    ● Ex.
    https://gist.github.ibm.com/cmluciano/b52e3764b3bdcb826ae37b039d9fb2
    be
    

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34. ReplicaSet
    ● Schedules new pods based on desired number
    ● Takes care of babysitting your pods and recreating whenever necessary
    ● Should be grouped together with labels as a selector
    ● Should most likely be used through a deployment
    ● Ex. https://gist.github.ibm.com/cmluciano/b52e3764b3bdcb826ae37b039d9fb2be
    

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35. Service
    ● Collect multiple pods together into related groupings based on labels
    ● RS front-end communicates with RS backend to create service X
    ● Creates an IP that represents the whole service and load balances
    appropriately
    

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36. Demo time
    ● Excellent
    

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37. Managed Kubernetes
    ● Bluemix.net
    

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38. IBM Cloud Kubernetes
    ● Native K8s APIs
    ● Fully managed HA installation
    ● IBM Cloud LoadBalancer
    ● Support for Ingress
    ● IBM Cloud registry
    ● Container security scanning
    ● Ease access to other IBM Cloud services like Watson and Compose.io
    

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39. Questions?
    ● Christopher M Luciano
    ● cmluciano@us.ibm.com
    ● github.com/cmluciano
    ● @cmluciano_ on Twitter
    

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