Knative: Serverless Workload on Kubernetes Mofi Rahman

@moficodes Level Set

@moficodes Microservices?

@moficodes Containers?

@moficodes Container Orchestration?

@moficodes Kubernetes?

@moficodes Serverless?

Mofizur Rahman Developer Advocate, IBM Do Container Stuff, Collect Stickers, Write go code @moficodes

@moficodes Agenda Learn About Knative and Why We Should Care See Some “Cool-ish” Demo Learn What’s to Come Next Be Impressed With Mofi

@moficodes Microservice Architecture ● Modular Software Development ● Small Services ● Independently Deployable

@moficodes Microservice Architecture ● Products not Projects ● Design for Failures ● Organized Around Business Capabilities

@moficodes It’s not just breaking down application into smaller parts.

@moficodes That would make “Distributed Monolith”

@moficodes Microservices and Containerization ● Better resource utilization ● Portable solution ● Container orchestration

@moficodes Why Kubernetes?

@moficodes Kubernetes Features ● Replicasets ● Horizontal Auto Scaling ● Health Check ● Self Healing ● Rolling Deployment ● Rollback ● Resource Quota ● Service Discovery ● Load Balancing ● Networking ● Cross Cloud ● Secret Management ● Batch Execution ● Storage orchestration

@moficodes What is Serverless?

@moficodes Serverless ● Any platform that can do on demand work. ● Run atomic (in theory) actions aka functions. ● Scales according to need

@moficodes Current Solutions: Pros and Cons Pros ● Good support and many choices ● Can handle many types of events ● Comparatively cheap Google Cloud Function, AWS Lambda, IBM Cloud Functions, Azure Functions etc. Cons ● Not much control in terms of hardware ● Can not really handle resource heavy work ● Completely separate platform

@moficodes Knative Pronounced Kay-nay-tive ** Not Native or Ki-native **

@moficodes What is Knative? Extends Kubernetes to provide a set of middleware components that are essential to modern app development The following Knative components are currently available: ● Eventing - Management and delivery of events ● Serving - Request-driven compute that can scale to zero

@moficodes Why Knative ● Serverless capabilities on K8s ● Extend K8s in a native way ● Higher level primitives ● More complete platform

@moficodes Serverless on K8s ● Full compute power of a cluster “on demand” ● Access to wide variety of hardware for serverless ● All on the same platform

@moficodes Extend K8s in a Native Way ● Make use of existing skills ● Get to use standard tools ● 3rd party tool support is better

@moficodes Higher Level Primitives ● Combines bunch of K8s operations in higher level primitives ● Enables automation

@moficodes Makes K8s More Complete With Knative K8s has ● Serverless ● Event streams ● Traffic Routing ● Monitoring ● Security (mTls) ● Policy Enforcement ● And all K8s things... Istio

@moficodes

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@moficodes

@moficodes Serving ● Uses Istio behind the scene ● Used for intelligent routing, blue-green deployment ● Scale down to zero ● Scale up to limit

@moficodes Demo

@moficodes

@moficodes Notes About Knative Build As of version v0.8 Knative build has been deprecated in favor of Tekton Pipeline

@moficodes Tekton Build Run on Kubernetes Have Kubernetes clusters as a first class type Use containers as their building blocks

@moficodes Tekton Primitives Task Defines a series of steps which launch specific build or delivery tools that ingest specific inputs and produce specific outputs. TaskRun Instantiates a Task for execution with specific inputs, outputs, and execution parameters. Can be invoked on its own or as part of a Pipeline. Pipeline Defines a series of Tasks that accomplish a specific build or delivery goal. Can be triggered by an event or invoked from a PipelineRun. PipelineResource Defines locations for inputs ingested and outputs produced by the steps in Tasks. PipelineRun Instantiates a Pipeline for execution with specific inputs, outputs, and execution parameters.

@moficodes Demo

@moficodes Blue/Green Deployment ● Gradually shift traffic from one version to a newer version Also See Canary Deployment, A/B Testing

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@moficodes 100% V1

@moficodes 100% V1 0% V2

@moficodes 100% V1 0% V2

@moficodes 50% V1 50% V2

@moficodes 0% V1 100% V2

@moficodes

@moficodes Demo

@moficodes Event Knative Eventing defines the following primitives: ● Event Sources ○ generate events from different sources (k8s, github, pub/sub, container) ● Channels ○ buffer between event producers and consumers ● Subscriptions ○ forward events from channels to services or other channels

@moficodes Eventing Principles 1. Services are loosely coupled 2. A producer can generate events before a consumer is listening, and a consumer can express an interest in an event or class of events that is not yet being produced. 3. Services can be connected to create new applications ○ without modifying producer or consumer. ○ with the ability to select a specific subset of events from a particular producer

@moficodes

@moficodes Knative on IKS

@moficodes Learn More at developer.ibm.com/tutoials/knative-101-labs https://knative.dev

@moficodes Whats Next?

Mofizur Rahman Developer Advocate, IBM @moficodes

@moficodes Thank You