c12s-kubespray/docs/aws-ebs-csi.md

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# AWS EBS CSI Driver
AWS EBS CSI driver allows you to provision EBS volumes for pods in EC2 instances. The old in-tree AWS cloud provider is deprecated and will be removed in future versions of Kubernetes. So transitioning to the CSI driver is advised.
To enable AWS EBS CSI driver, uncomment the `aws_ebs_csi_enabled` option in `group_vars/all/aws.yml` and set it to `true`.
To set the number of replicas for the AWS CSI controller, you can change `aws_ebs_csi_controller_replicas` option in `group_vars/all/aws.yml`.
Make sure to add a role, for your EC2 instances hosting Kubernetes, that allows it to do the actions necessary to request a volume and attach it: [AWS CSI Policy](https://github.com/kubernetes-sigs/aws-ebs-csi-driver/blob/master/docs/example-iam-policy.json)
If you want to deploy the AWS EBS storage class used with the CSI Driver, you should set `persistent_volumes_enabled` in `group_vars/k8s-cluster/k8s-cluster.yml` to `true`.
You can now run the kubespray playbook (cluster.yml) to deploy Kubernetes over AWS EC2 with EBS CSI Driver enabled.
## Usage example
To check if AWS EBS CSI Driver is deployed properly, check that the ebs-csi pods are running:
```ShellSession
$ kubectl -n kube-system get pods | grep ebs
ebs-csi-controller-85d86bccc5-8gtq5 4/4 Running 4 40s
ebs-csi-node-n4b99 3/3 Running 3 40s
```
Check the associated storage class (if you enabled persistent_volumes):
```ShellSession
$ kubectl get storageclass
NAME PROVISIONER AGE
ebs-sc ebs.csi.aws.com 45s
```
You can run a PVC and an example Pod using this file `ebs-pod.yml`:
```yml
--
apiVersion: v1
kind: PersistentVolumeClaim
metadata:
name: ebs-claim
spec:
accessModes:
- ReadWriteOnce
storageClassName: ebs-sc
resources:
requests:
storage: 1Gi
---
apiVersion: v1
kind: Pod
metadata:
name: app
spec:
containers:
- name: app
image: centos
command: ["/bin/sh"]
args: ["-c", "while true; do echo $(date -u) >> /data/out.txt; sleep 5; done"]
volumeMounts:
- name: persistent-storage
mountPath: /data
volumes:
- name: persistent-storage
persistentVolumeClaim:
claimName: ebs-claim
```
Apply this conf to your cluster: ```kubectl apply -f ebs-pod.yml```
You should see the PVC provisioned and bound:
```ShellSession
$ kubectl get pvc
NAME STATUS VOLUME CAPACITY ACCESS MODES STORAGECLASS AGE
ebs-claim Bound pvc-0034cb9e-1ddd-4b3f-bb9e-0b5edbf5194c 1Gi RWO ebs-sc 50s
```
And the volume mounted to the example Pod (wait until the Pod is Running):
```ShellSession
$ kubectl exec -it app -- df -h | grep data
/dev/nvme1n1 1014M 34M 981M 4% /data
```
## More info
For further information about the AWS EBS CSI Driver, you can refer to this page: [AWS EBS Driver](https://github.com/kubernetes-sigs/aws-ebs-csi-driver/).