Amazon Elastic Block Store (EBS) CSI driver

Overview

The Amazon Elastic Block Store Container Storage Interface (CSI) Driver provides a CSI interface used by Container Orchestrators to manage the lifecycle of Amazon EBS volumes.

CSI Specification Compability Matrix

AWS EBS CSI Driver \ CSI Version	v0.3.0	v1.0.0	v1.1.0
master branch	no	no	yes
v0.7.0	no	no	yes
v0.6.0	no	no	yes
v0.5.0	no	no	yes
v0.4.0	no	no	yes
v0.3.0	no	yes	no
v0.2.0	no	yes	no
v0.1.0	yes	no	no

Features

The following CSI gRPC calls are implemented:

• Controller Service: CreateVolume, DeleteVolume, ControllerPublishVolume, ControllerUnpublishVolume, ControllerGetCapabilities, ValidateVolumeCapabilities, CreateSnapshot, DeleteSnapshot, ListSnapshots
• Node Service: NodeStageVolume, NodeUnstageVolume, NodePublishVolume, NodeUnpublishVolume, NodeGetCapabilities, NodeGetInfo
• Identity Service: GetPluginInfo, GetPluginCapabilities, Probe

CreateVolume Parameters

There are several optional parameters that could be passed into CreateVolumeRequest.parameters map:

Parameters	Values	Default	Description
"csi.storage.k8s.io/fsType"	xfs, ext2, ext3, ext4	ext4	File system type that will be formatted during volume creation
"type"	io1, io2, gp2, sc1, st1,standard	gp2	EBS volume type
"iopsPerGB"			I/O operations per second per GiB. Required when io1 or io2 volume type is specified
"encrypted"			Whether the volume should be encrypted or not. Valid values are "true" or "false"
"kmsKeyId"			The full ARN of the key to use when encrypting the volume. When not specified, the default KMS key is used

Notes:

• The parameters are case insensitive.

EBS CSI Driver on Kubernetes

Following sections are Kubernetes specific. If you are Kubernetes user, use followings for driver features, installation steps and examples.

Kubernetes Version Compability Matrix

| AWS EBS CSI Driver \ Kubernetes Version| v1.12 | v1.13 | v1.14 | v1.15 | v1.16 | v1.17 | v1.18 | |----------------------------------------|-------|-------|-------|-------|-------|---------------- | master branch | no | no+ | yes | yes | yes | yes | yes | | v0.7.0 | no | no+ | yes | yes | yes | yes | yes | | v0.6.0 | no | no+ | yes | yes | yes | yes | yes | | v0.5.0 | no | no+ | yes | yes | yes | yes | yes | | v0.4.0 | no | no+ | yes | yes | no | no | no | | v0.3.0 | no | no+ | yes | no | no | no | no | | v0.2.0 | no | yes | yes | no | no | no | no | | v0.1.0 | yes | yes | yes | no | no | no | no |

Note: for the entry with + sign, it means the driver's default released manifest doesn't work with corresponding Kubernetes version, but the driver container image is compatiable with the Kubernetes version if an older version's manifest is used.

Container Images:

AWS EBS CSI Driver Version	Image
master branch	amazon/aws-ebs-csi-driver:latest
v0.7.0	amazon/aws-ebs-csi-driver:v0.7.0
v0.6.0	amazon/aws-ebs-csi-driver:v0.6.0
v0.5.0	amazon/aws-ebs-csi-driver:v0.5.0
v0.4.0	amazon/aws-ebs-csi-driver:v0.4.0
v0.3.0	amazon/aws-ebs-csi-driver:v0.3.0
v0.2.0	amazon/aws-ebs-csi-driver:0.2.0
v0.1.0	amazon/aws-ebs-csi-driver:0.1.0-alpha

Features

• Static Provisioning - create a new or migrating existing EBS volumes, then create persistence volume (PV) from the EBS volume and consume the PV from container using persistence volume claim (PVC).
• Dynamic Provisioning - uses persistence volume claim (PVC) to request the Kuberenetes to create the EBS volume on behalf of user and consumes the volume from inside container. Storage class's allowedTopologies could be used to restrict which AZ the volume should be provisioned in. The topology key should be topology.ebs.csi.aws.com/zone.
• Mount Option - mount options could be specified in persistence volume (PV) to define how the volume should be mounted.
• NVMe - consume NVMe EBS volume from EC2 Nitro instance.
• Block Volume - consumes the EBS volume as a raw block device for latency sensitive application eg. MySql. The corresponding CSI feature (CSIBlockVolume) is GA since Kubernetes 1.18.
• Volume Snapshot - creating volume snapshots and restore volume from snapshot. The corresponding CSI feature (VolumeSnapshotDataSource) is beta since Kubernetes 1.17.
• Volume Resizing - expand the volume size. The corresponding CSI feature (ExpandCSIVolumes) is beta since Kubernetes 1.16.

Prerequisites

• If you are managing EBS volumes using static provisioning, get yourself familiar with EBS volume.
• Get yourself familiar with how to setup Kubernetes on AWS and have a working Kubernetes cluster:
  • Enable flag --allow-privileged=true for kubelet and kube-apiserver
  • Enable kube-apiserver feature gates --feature-gates=CSINodeInfo=true,CSIDriverRegistry=true,CSIBlockVolume=true,VolumeSnapshotDataSource=true
  • Enable kubelet feature gates --feature-gates=CSINodeInfo=true,CSIDriverRegistry=true,CSIBlockVolume=true

Installation

Set up driver permission

The driver requires IAM permission to talk to Amazon EBS to manage the volume on user's behalf. There are several methods to grant driver IAM permission:

• Using secret object - create an IAM user with proper permission, put that user's credentials in secret manifest then deploy the secret.

curl https://raw.githubusercontent.com/kubernetes-sigs/aws-ebs-csi-driver/master/deploy/kubernetes/secret.yaml > secret.yaml
# Edit the secret with user credentials
kubectl apply -f secret.yaml

• Using IAM instance profile - grant all the worker nodes with proper permission by attaching policy to the instance profile of the worker.

Deploy CRD (optional)

If your cluster is v1.14+, you can skip this step. Install the CSINodeInfo CRD on the cluster:

kubectl create -f https://raw.githubusercontent.com/kubernetes/csi-api/release-1.13/pkg/crd/manifests/csinodeinfo.yaml

Deploy driver

If you want to deploy the stable driver without alpha features:

kubectl apply -k "github.com/kubernetes-sigs/aws-ebs-csi-driver/deploy/kubernetes/overlays/stable/?ref=master"

If you want to deploy the driver with alpha features:

kubectl apply -k "github.com/kubernetes-sigs/aws-ebs-csi-driver/deploy/kubernetes/overlays/alpha/?ref=master"

Verify driver is running:

kubectl get pods -n kube-system

Alternatively, you could also install the driver using helm:

helm install \
    --namespace kube-system \
    --name aws-ebs-csi-driver \
    --set enableVolumeScheduling=true \
    --set enableVolumeResizing=true \
    --set enableVolumeSnapshot=true \
    https://github.com/kubernetes-sigs/aws-ebs-csi-driver/releases/download/v0.7.0/helm-chart.tgz

Examples

Make sure you follow the Prerequisites before the examples:

• Dynamic Provisioning
• Block Volume
• Volume Snapshot
• Configure StorageClass
• Volume Resizing

Migrating from in-tree EBS plugin

Starting from Kubernetes 1.17, CSI migration is supported as beta feature (alpha since 1.14). If you have persistence volumes that are created with in-tree kubernetes.io/aws-ebs plugin, you could migrate to use EBS CSI driver. To turn on the migration, set CSIMigration and CSIMigrationAWS feature gates to true for kube-controller-manager and kubelet.

To make sure dynamically provisioned EBS volumes have all tags that the in-tree volume plugin used:

• Run the external-provisioner sidecar with --extra-create-metadata=true cmdline option. External-provisioner v1.6 or newer is required.
• Run the CSI driver with --k8s-tag-cluster-id=<ID of the Kubernetes cluster> command line option.

Development

Please go through CSI Spec and General CSI driver development guideline to get some basic understanding of CSI driver before you start.

Requirements

• Golang 1.14.+
• Ginkgo in your PATH for integration testing and end-to-end testing
• Docker 17.05+ for releasing

Dependency

Dependencies are managed through go module. To build the project, first turn on go mod using export GO111MODULE=on, then build the project using: make

Testing

• To execute all unit tests, run: make test
• To execute sanity test run: make test-sanity
• To execute integration tests, run: make test-integration
• To execute e2e tests, run: make test-e2e-single-az and make test-e2e-multi-az

Notes:

• Sanity tests make sure the driver complies with the CSI specification
• EC2 instance is required to run integration test, since it is exercising the actual flow of creating EBS volume, attaching it and read/write on the disk. See Integration Testing for more details.
• E2E tests exercises various driver functionalities in Kubernetes cluster. See E2E Testing for more details.

Build and Publish Container Image

• Build image and push it with latest tag: make image && make push
• Build image and push it with release tag: make image-release && make push-release

Helm and manifests

The helm chart for this project is in the aws-ebs-csi-driver directory. The manifests for this project are in the deploy/kubernetes directory. All of the manifests except kustomize patches are generated by running helm template. This keeps the helm chart and the manifests in sync.

When updating the helm chart:

• Generate manifests: make generate-kustomize
• There are values files in deploy/kubernetes/values used for generating some of the manifests
• When adding a new resource template to the helm chart please update the generate-kustomize make target, the deploy/kubernetes/values files, and the appropriate kustomization.yaml file(s).

Milestone

Milestones page