Intro to Kubernetes Christopher M Luciano 

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 

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

Building an Application My application 

Deploying Super_bash_script_deluxe.sh Upgrade_to_the_max.sh 

Deploying better_upgrader_in_python.py 

Deploying Better_upgrader_in_python_tests.py Better_upgrader_in_python_tests_with_awesomeframework.py 

Problem Stacks On Stacks On Stacks 

Running an Application start_it_up.sh 

Running an Application 

Running an Application 

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

Scaling an Application Great Success!!! 

Scaling an Application Great Success!!! 

Scaling an Application More traffic, more power 

Scaling an Application Not enough traffic, need less servers 

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

Upgrading an application 

Upgrading an application Display update 5 of 20 machines 

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

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

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

Scheduling an Application One application to rule, them all 

Scheduling an Application 

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

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

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 

Kubernetes Welcome to The Presentation 

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 

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 

Core Concepts 

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

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 

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 

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 

Demo time ● Excellent 

Managed Kubernetes ● Bluemix.net 

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 

Questions? ● Christopher M Luciano ● [email protected] ● github.com/cmluciano ● @cmluciano_ on Twitter