Serverless

• Serverles architecture generally describes fully managed cloud services

• The classifiction of a cloud service being serverless is not boolean answer (yes or no)

• Answer is on scale where cloud service has degree of serverless

Characteristics

• Higly scalable

• Higly available

• Higly Durable

• Secure by default

• Billed based on business tasks

• Can scale to zero

• Pay for value (You don't pay for ideal server)

Function as a Service (FaaS):

• Allows developers to focus on just writing pieces of code (functions)

• Generally multiple functions are orchastrated together to create a serverless app.

• Functions only run when needed

1. OpenFaaS:

• Runs serverless function anywhere Docker runs

2. Faasd:

• It is light weight version of OpenFaaS that doesn't need Kubernetes to run.

• It can run on single under-powered machine

3. Apache OpenWisk:

• Deploy to Kubernetes, Mesos, Docker Swarm

KNative:

• Kubernetes-based platform to deploy and manage modern serverless workloads

• KNative is a project to create a standard set of building blocks for kubernetes to enable serverless deployment patter

• KNative generally is composed of two parts

  • KNative serving:

    • Take containerized code and eploy it with relative ease

    • Scale to zero cost

  • KNative Eventing:

    • Trigger serverless function based on K8s API events.

• Considerations:

  • Not a complete serverless function

  • It does not offere FaaS offereingd

• KNative defines its own set of Kubernetes objects as kubernetes custom resource definitions (CRDs)

• KNative Components:

  • Service

  • Route

  • Configuration

  • Revision

• KNative uses its own CLI called kn used alongside kubectl

💡 You should definitly read about KNative v/s OpenFaaS once

Serverless