index.rst

Installation

development rbac

The following directions will walk through the process of deploying VolSync.

Note

Volume snapshot and clone capabilities are required for some VolSync functionality. It is recommended that you use a CSI driver and StorageClass capable of snapshotting and cloning volumes.

There are several methods for installing VolSync. Choose the option that relates to your situation.

Warning

VolSync requires the Kubernetes snapshot controller to be installed within a cluster. If the controller is not deployed review the snapshot controller documentation https://github.com/kubernetes-csi/external-snapshotter.

Kubernetes & OpenShift

The recommended method for deploying VolSync is via its Helm chart.

# Add the Backube Helm repo
$ helm repo add backube https://backube.github.io/helm-charts/

# Deploy the chart in your cluster
$ helm install --create-namespace -n volsync-system volsync backube/volsync

Verify VolSync is running by checking the output of kubectl get deploy:

$ kubectl -n volsync-system get deploy/volsync
NAME      READY   UP-TO-DATE   AVAILABLE   AGE
volsync   1/1     1            1           60s

Configuring CSI storage

To make the most of VolSync's capabilities, it's important that the volumes being replicated are using CSI-based storage drivers and that volume snapshotting is properly configured.

The currently configured StorageClasses can be viewed via:

$ kubectl get storageclasses

And the VolumeSnapshotClasses can be viewed via:

$ kubectl get volumesnapshotclasses

StorageClasses that carry the storageclass.kubernetes.io/is-default-class: "true" and VolumeSnapshotClasses that carry the snapshot.storage.kubernetes.io/is-default-class: "true" annotations are marked as the defaults on the cluster, meaning that if the class is not specified, these defaults will be used. However, it is not necessary to set or modify the default on your cluster since the classes can be specified directly in the ReplicationSource and ReplicationDestination objects used by VolSync.

Below are examples of configured CSI storage on a few different platforms. Your configuration may be different.

AWS

The EBS CSI driver on AWS-based clusters is usually named gp2-csi or gp3-csi.

# List StorageClasses
$ kubectl get storageclasses
NAME            PROVISIONER             RECLAIMPOLICY   VOLUMEBINDINGMODE      ALLOWVOLUMEEXPANSION   AGE
gp2 (default)   kubernetes.io/aws-ebs   Delete          WaitForFirstConsumer   true                   25m
gp2-csi         ebs.csi.aws.com         Delete          WaitForFirstConsumer   true                   25m
gp3-csi         ebs.csi.aws.com         Delete          WaitForFirstConsumer   true                   25m


# View details of the gp2-csi SC
$ kubectl get storageclass/gp2-csi -oyaml
allowVolumeExpansion: true
apiVersion: storage.k8s.io/v1
kind: StorageClass
metadata:
   creationTimestamp: "2022-02-08T14:03:20Z"
   name: gp2-csi
   resourceVersion: "5288"
   uid: 24d2cee6-1346-4c3e-8742-39dec08e3e50
parameters:
   encrypted: "true"
   type: gp2
provisioner: ebs.csi.aws.com
reclaimPolicy: Delete
volumeBindingMode: WaitForFirstConsumer

Azure

The CSI driver on Azure-based clusters is usually named managed-csi.

# List StorageClasses
$ kubectl get storageclasses
NAME                        PROVISIONER                RECLAIMPOLICY   VOLUMEBINDINGMODE      ALLOWVOLUMEEXPANSION   AGE
managed-csi                 disk.csi.azure.com         Delete          WaitForFirstConsumer   true                   45m
managed-premium (default)   kubernetes.io/azure-disk   Delete          WaitForFirstConsumer   true                   46m

# View details of the managed-csi SC
$ kubectl get storageclass/managed-csi -oyaml
allowVolumeExpansion: true
apiVersion: storage.k8s.io/v1
kind: StorageClass
metadata:
   creationTimestamp: "2022-02-08T14:57:23Z"
   name: managed-csi
   resourceVersion: "5853"
   uid: 3aeba0d1-6c52-481c-9dc1-786ae84a2f7b
parameters:
   skuname: Premium_LRS
provisioner: disk.csi.azure.com
reclaimPolicy: Delete
volumeBindingMode: WaitForFirstConsumer

GCP

The CSI driver on GCP-based clusters is usually named standard-csi.

# List StorageClasses
$ kubectl get storageclasses
NAME                 PROVISIONER             RECLAIMPOLICY   VOLUMEBINDINGMODE      ALLOWVOLUMEEXPANSION   AGE
standard (default)   kubernetes.io/gce-pd    Delete          WaitForFirstConsumer   true                   15m
standard-csi         pd.csi.storage.gke.io   Delete          WaitForFirstConsumer   true                   15m


# View details of the standard-csi SC
$ kubectl get storageclass/standard-csi -oyaml
allowVolumeExpansion: true
apiVersion: storage.k8s.io/v1
kind: StorageClass
metadata:
   creationTimestamp: "2022-02-08T13:24:53Z"
   name: standard-csi
   resourceVersion: "5976"
   uid: 066a43fc-798f-49a7-b62a-0350e8946364
parameters:
   replication-type: none
   type: pd-standard
provisioner: pd.csi.storage.gke.io
reclaimPolicy: Delete
volumeBindingMode: WaitForFirstConsumer

Longhorn

The CSI driver on Longhorn-based clusters are configured based on the underlying storage type. Here, we will assume a default StorageClass named longhorn.

# List StorageClasses
$ kubectl get storageclasses
NAME                 PROVISIONER             RECLAIMPOLICY   VOLUMEBINDINGMODE      ALLOWVOLUMEEXPANSION   AGE
longhorn (default)   driver.longhorn.io      Delete          Immediate              true                   15m


# View details of the longhorn SC
$ kubectl get storageclass/longhorn -oyaml
kind: StorageClass
apiVersion: storage.k8s.io/v1
metadata:
  name: longhorn
provisioner: driver.longhorn.io
allowVolumeExpansion: true
reclaimPolicy: Delete
volumeBindingMode: Immediate
parameters:
  # Your parameters here...

vSphere

The CSI driver on vSphere-based clusters is usually named thin-csi.

# List StorageClasses
$ kubectl get storageclasses
NAME             PROVISIONER                    RECLAIMPOLICY   VOLUMEBINDINGMODE      ALLOWVOLUMEEXPANSION   AGE
thin (default)   kubernetes.io/vsphere-volume   Delete          Immediate              false                  20m
thin-csi         csi.vsphere.vmware.com         Delete          WaitForFirstConsumer   true                   18m

# View details of the thin-csi SC
$ kubectl get storageclass/thin-csi -oyaml
allowVolumeExpansion: true
apiVersion: storage.k8s.io/v1
kind: StorageClass
metadata:
   creationTimestamp: "2022-02-08T16:48:52Z"
   name: thin-csi
   resourceVersion: "9789"
   uid: 80d45374-8447-47eb-950c-2568af070d6e
parameters:
   StoragePolicyName: openshift-storage-policy-ci-ln-54d2r5t-c1627-jvkws
provisioner: csi.vsphere.vmware.com
reclaimPolicy: Delete
volumeBindingMode: WaitForFirstConsumer

You should also verify the presence of a corresponding VolumeSnapshotClass. Note that the name of the SC and VSC do not need to be the same, but the provisioner/driver should be.

AWS

# List VolumeSnapshotClasses
$ kubectl get volumesnapshotclasses
NAME          DRIVER            DELETIONPOLICY   AGE
csi-aws-vsc   ebs.csi.aws.com   Delete           23m


# View details of the csi-aws-vsc VSC
$ kubectl get volumesnapshotclass/csi-aws-vsc -oyaml
apiVersion: snapshot.storage.k8s.io/v1
deletionPolicy: Delete
driver: ebs.csi.aws.com
kind: VolumeSnapshotClass
metadata:
   annotations:
      snapshot.storage.kubernetes.io/is-default-class: "true"
   creationTimestamp: "2022-02-08T14:03:20Z"
   generation: 1
   name: csi-aws-vsc
   resourceVersion: "5301"
   uid: d990af7b-d2ae-4a49-8cfe-fd5ae93902df

Important

The AWS EBS CSI driver does not support volume cloning. When configuring replication with VolSync, be sure to choose a copyMethod of Snapshot for the source volume. Choosing Clone will not work.

Azure

# List VolumeSnapshotClasses
$ kubectl get volumesnapshotclasses
NAME                DRIVER               DELETIONPOLICY   AGE
csi-azuredisk-vsc   disk.csi.azure.com   Delete           48m

# View details of the csi-azuredisk-vsc VSC
$ kubectl get volumesnapshotclass/csi-azuredisk-vsc -oyaml
apiVersion: snapshot.storage.k8s.io/v1
deletionPolicy: Delete
driver: disk.csi.azure.com
kind: VolumeSnapshotClass
metadata:
   annotations:
      snapshot.storage.kubernetes.io/is-default-class: "true"
   creationTimestamp: "2022-02-08T14:57:23Z"
   generation: 1
   name: csi-azuredisk-vsc
   resourceVersion: "5847"
   uid: 1d105f8c-4e49-48e1-8ead-927f90f4bb2e
parameters:
   incremental: "true"

GCP

# List VolumeSnapshotClasses
$ kubectl get volumesnapshotclasses
NAME             DRIVER                  DELETIONPOLICY   AGE
csi-gce-pd-vsc   pd.csi.storage.gke.io   Delete           17m


# View details of the csi-gce-pd-vsc VSC
$ kubectl get volumesnapshotclass/csi-gce-pd-vsc -oyaml
apiVersion: snapshot.storage.k8s.io/v1
deletionPolicy: Delete
driver: pd.csi.storage.gke.io
kind: VolumeSnapshotClass
metadata:
   annotations:
      snapshot.storage.kubernetes.io/is-default-class: "true"
   creationTimestamp: "2022-02-08T13:24:53Z"
   generation: 1
   name: csi-gce-pd-vsc
   resourceVersion: "5981"
   uid: 886de96d-820c-403b-8570-fcfb37939532

Longhorn

# List VolumeSnapshotClasses
$ kubectl get volumesnapshotclasses
NAME                    DRIVER                  DELETIONPOLICY   AGE
longhorn-snapshot-vsc   driver.longhorn.io      Delete           10m


# View details of the longhorn-snapshot-vsc VSC
$ kubectl get volumesnapshotclass/longhorn-snapshot-vsc -oyaml
kind: VolumeSnapshotClass
apiVersion: snapshot.storage.k8s.io/v1
metadata:
  annotations:
    snapshot.storage.kubernetes.io/is-default-class: "true"
  name: longhorn-snapshot-vsc
driver: driver.longhorn.io
deletionPolicy: Delete
parameters:
  type: snap  # a CSI snapshot maps to a Longhorn snapshot

For more information on configuring Longhorn snapshots, see the Longhorn documentation.

vSphere

At this time (Feb 2022), volume snapshotting is an alpha feature in the vSphere CSI driver and not enabled by default. If you are interested in trying it out, please consult VMware's documentation.

Next, consider granting users access to VolSync's custom resources <rbac> so that they can manage their own data replication.

Continue to the usage docs </usage/index>.