K8s Spot Termination Handler

This repository has been DEPRECATED and we recommend using the official AWS Node Termination Handler from AWS instead. See #14 regarding ownership of this repository.

Table of contents

• Introduction
• Usage
• Related
• Communication
• Contributing
• License

Introduction

The K8s Spot Termination handler watches the AWS metadata service when running on Spot Instances.

When a Spot Instance is due to be terminated, precisely 2 minutes before it's termination a "termination notice" is issued. The K8s Spot Termination Handler watches for this and then gracefully drains the node it is running on before the node is taken away by AWS.

Usage

Deploy to Kubernetes

A docker image is available at quay.io/pusher/k8s-spot-termination-handler. These images are currently built on pushes to master. Releases will be tagged as and when releases are made.

Sample Kubernetes manifests are available in the deploy folder.

To deploy in clusters using RBAC, please apply all of the manifests (Daemonset, ClusterRole, ClusterRoleBinding and ServiceAccount) in the deploy folder but uncomment the serviceAccountName in the Daemonset.

Requirements

For the K8s Termination Handler to schedule correctly; you will need an identifying label on your spot instances.

We add a label node-role.kubernetes.io/spot-worker to our spot instances and hence this is the default value in the node selector of the Daemonset.

nodeSelector:
  "node-role.kubernetes.io/spot-worker": "true"

To achieve this, add the following flag to your Kubelet:

--node-labels="node-role.kubernetes.io/spot-worker=true"

Configuration

To define any custom parameters to the drain command you can use DRAIN_PARAMETERS environment property. If not defined, default parameters are --grace-period=120 --force --ignore-daemonsets.

env:
  - name: DRAIN_PARAMETERS
    value: '--grace-period=120 --force --ignore-daemonsets --delete-local-data'

Related

• K8s Spot Rescheduler: Move nodes from on-demand instances to spot instances when space is available.

Communication

• Found a bug? Please open an issue.
• Have a feature request. Please open an issue.
• If you want to contribute, please submit a pull request

Contributing

Please see our Contributing guidelines.

License

This project is licensed under Apache 2.0 and a copy of the license is available here.