Kubernetes on AWS

WORK IN PROGRESS

This repo contains configuration templates to provision Kubernetes clusters on AWS using Cloud Formation and CoreOS Container Linux.

Consider this as alpha quality. Many values are hardcoded, and currently we're focusing on solving our own, specific/Zalando use case. However, we are open to ideas from the community at large about potentially turning this idea into a project that provides universal/general value to others. Please contact us via our Issues Tracker with your thoughts and suggestions.

Configuration in this repository initially was based on kube-aws, but now depends on three components which are not yet open sourced:

• Cluster Registry to keep desired cluster states (e.g. used config channel and version)
• Cluster Lifecycle Manager to provision the cluster's Cloud Formation stack and apply Kubernetes manifests for system components
• Authnz Webhook to validate OAuth tokens and authorize access

We plan to release all required components to the community in Q2/2017.

Please watch our meetup talk "Kubernetes on AWS at Europe's Leading Online Fashion Platform" on YouTube to learn how we run Kubernetes on AWS in production. See our Running Kubernetes in Production on AWS document for details on the setup.

Features

• Highly available master nodes (ASG) behind ELB
• Worker Auto Scaling Group
• Flannel overlay networking
• Cluster autoscaling (using kube-aws-autoscaler)
• Route53 DNS integration via External DNS
• AWS IAM integration via kube2iam
• Standard components are installed: kube-dns, heapster, dashboard, node exporter, kube-state-metrics
• Webhook authentication and authorization (roles "ReadOnly", "PowerUser", "Administrator")
• Log shipping via Scalyr
• Full Ingress support with ALB/SSL via kube-ingress-aws-controller
• Planned: Spot Fleet integration (#61)

Notes

• Node and user authentication is done via tokens (using the webhook feature)
• SSL client-cert authentication is disabled
• Many values are hardcoded
• Secrets (e.g. shared token) are not KMS-encrypted

Assumptions

• The AWS account has a single Route53 hosted zone including a proper SSL cert (you can use the free ACM service)
• The VPC has at least one public subnet per AZ (either AWS default VPC setup or public subnet named "dmz-<REGION>-<AZ>")
• The VPC is in region eu-central-1 or eu-west-1
• etcd cluster is available via DNS discovery (SRV records) at etcd.<YOUR-HOSTED-ZONE>
• OAuth Token Info is available to validate user tokens

Directory Structure

• cluster: Senza Cloud Formation files and userdata (cloud-init) for ContainerLinux nodes
• cluster/manifests: Kubernetes manifests for system components (will be applied by Cluster Lifecycle Manager)
• docs: extracts from internal Zalando documentation (https://kubernetes-on-aws.readthedocs.io/)