This topic describes how to use Velero to back up and restore a stateful application using the namespace feature with Velero.
Overview
This example demonstrates Velero back up and restore for a stateful application using namespace.
To test Velero back up and restore for stateful applications, use the Guestbook application with a persistent volume.
When restoring the stateful application using Velero, the Storage Class that was used by the PVC in the application must be present on the Kubernetes cluster. If the PVC is using the default storage class, then the default storage class must also be present prior to initiating the restore operation with Velero.
Prerequisites
Install and configure MinIO, Velero, and restic.
Download the Guestbook app YAML files to a local known directory:
- redis-leader-deployment.yaml
- redis-leader-service.yaml
- redis-follower-deployment.yaml
- redis-follower-service.yaml
- frontend-deployment.yaml
- frontend-service.yaml
Deploy Guestbook App
Create the default storage class named redis-sc.yaml:
kind: StorageClass
apiVersion: storage.k8s.io/v1
metadata:
name: thin-disk
annotations:
storageclass.kubernetes.io/is-default-class: "true"
provisioner: kubernetes.io/vsphere-volume
parameters:
diskformat: thin
Apply the YAML file:
kubectl apply -f redis-sc.yaml
storageclass.storage.k8s.io/thin-disk created
Verify the storage class:
kubectl get sc
NAME PROVISIONER RECLAIMPOLICY VOLUMEBINDINGMODE ALLOWVOLUMEEXPANSION AGE
thin-disk (default) kubernetes.io/vsphere-volume Delete Immediate false 4s
Create Guestbook namespace:
kubectl create ns guestbook-pv
namespace/guestbook-pv created
Deploy the Guestbook app:
kubectl apply -f . -n guestbook-pv
storageclass.storage.k8s.io/thin-disk unchanged
persistentvolumeclaim/redis-leader-claim created
persistentvolumeclaim/redis-follower-claim created
service/redis-leader created
deployment.apps/redis-leader created
service/redis-follower created
deployment.apps/redis-follower created
service/frontend created
deployment.apps/frontend created
Verify:
kubectl get all -n guestbook-pv
NAME READY STATUS RESTARTS AGE
frontend-6cb7f8bd65-kqbf6 1/1 Running 0 38s
frontend-6cb7f8bd65-s7mk9 1/1 Running 0 38s
frontend-6cb7f8bd65-vtz4k 1/1 Running 0 38s
redis-leader-7b8487bf68-2mhcd 1/1 Running 0 38s
redis-follower-5bdcfd74c7-4hhqs 1/1 Running 0 37s
redis-follower-5bdcfd74c7-hl8hf 1/1 Running 0 37s
kubectl get pvc,pv -n guestbook-pv
NAME STATUS VOLUME CAPACITY ACCESS MODES STORAGECLASS AGE
persistentvolumeclaim/redis-leader-claim Bound pvc-e0f3b455-e66e-45e6-8f77-4ace5af0ce6a 2Gi RWO thin-disk 2m31s
persistentvolumeclaim/redis-follower-claim Bound pvc-672ab412-1167-4110-87cc-51c2bfedfa18 2Gi RWO thin-disk 2m31s
NAME CAPACITY ACCESS MODES RECLAIM POLICY STATUS CLAIM STORAGECLASS REASON AGE
persistentvolume/pvc-672ab412-1167-4110-87cc-51c2bfedfa18 2Gi RWO Delete Bound guestbook-pv/redis-follower-claim thin-disk 2m30s
persistentvolume/pvc-e0f3b455-e66e-45e6-8f77-4ace5af0ce6a 2Gi RWO Delete Bound guestbook-pv/redis-leader-claim thin-disk 2m30s
Access the Guestbook app at http://10.199.41.14/.
Add many messages so they can be stored in the PV.
Back Up the Guestbook App Using Namespace
This example shows how to back up and restore the Guestbook app using the --include namespace tag.
Because this app is stateful, you need to add annotations for the stateful pods with the volume name.
Get the volume names:
kubectl get pod -n guestbook-pv
NAME READY STATUS RESTARTS AGE
frontend-6cb7f8bd65-9cpdc 1/1 Running 0 6m27s
frontend-6cb7f8bd65-h2pnb 1/1 Running 0 6m27s
frontend-6cb7f8bd65-kwlpr 1/1 Running 0 6m27s
frontend-6cb7f8bd65-snwl4 1/1 Running 0 6m27s
redis-leader-64fb8775bf-kbs6s 1/1 Running 0 6m28s
redis-follower-779b6d8f79-5dphr 1/1 Running 0 6m28s
The volume name is redis-leader-data for pod redis-leader-64fb8775bf-kbs6s.
The volume name is redis-follower-data for pod redis-follower-779b6d8f79-5dphr.
Annotate the pods:
kubectl -n guestbook-pv annotate pod redis-leader-64fb8775bf-kbs6s backup.velero.io/backup-volumes=redis-leader-data
pod/redis-leader-64fb8775bf-kbs6s annotated
kubectl -n guestbook-pv annotate pod redis-follower-779b6d8f79-5dphr backup.velero.io/backup-volumes=redis-follower-data
pod/redis-follower-779b6d8f79-5dphr annotated
Verify:
kubectl -n guestbook-pv describe pod redis-leader-64fb8775bf-kbs6s | grep Annotations
Annotations: backup.velero.io/backup-volumes: redis-leader-data
kubectl -n guestbook-pv describe pod redis-follower-779b6d8f79-5dphr | grep Annotations
Annotations: backup.velero.io/backup-volumes: redis-follower-data
velero backup create guestbook-backup --include-namespaces guestbook
Perform the Velero back up:
velero backup create guestbook-pv-backup --include-namespaces guestbook-pv
Backup request "guestbook-pv-backup" submitted successfully.
Run `velero backup describe guestbook-pv-backup` or `velero backup logs guestbook-pv-backup` for more details.
Verify the backup that was created.
velero backup get
NAME STATUS ERRORS WARNINGS CREATED EXPIRES STORAGE LOCATION SELECTOR
guestbook-pv-backup Completed 0 0 2020-07-23 16:13:46 -0700 PDT 29d default <none>
Verify backup details:
velero backup describe guestbook-pv-backup --details
The Velero Kubernetes CustomResourceDefinitions (CRDs) let you run certain commands, such as the following:
kubectl get backups.velero.io -n velero
NAME AGE
guestbook-backup 4m58s
kubectl describe backups.velero.io guestbook-pv-backup -n velero
Restore the Guestbook App
To test the restoration of the Guestbook app, delete it.
Delete the namespace:
kubectl delete ns guestbook-pv
namespace "guestbook-pv" deleted
Verify namespace deletion:
kubectl get ns
kubectl get pvc,pv --all-namespaces
Make sure the storage class used by the application is still present:
kubectl get sc
NAME PROVISIONER RECLAIMPOLICY VOLUMEBINDINGMODE ALLOWVOLUMEEXPANSION AGE
thin-disk (default) kubernetes.io/vsphere-volume Delete Immediate false 26m
Restore the app:
velero restore create --from-backup guestbook-pv-backup
Restore request "guestbook-pv-backup-20200723161841" submitted successfully.
Run `velero restore describe guestbook-pv-backup-20200723161841` or `velero restore logs guestbook-pv-backup-20200723161841` for more details.
Verify that the app is restored:
velero restore describe guestbook-pv-backup-20200723161841
Name: guestbook-pv-backup-20200723161841
Namespace: velero
Labels: <none>
Annotations: <none>
Phase: Completed
Backup: guestbook-pv-backup
Namespaces:
Included: all namespaces found in the backup
Excluded: <none>
Resources:
Included: *
Excluded: nodes, events, events.events.k8s.io, backups.velero.io, restores.velero.io, resticrepositories.velero.io
Cluster-scoped: auto
Namespace mappings: <none>
Label selector: <none>
Restore PVs: auto
Restic Restores (specify --details for more information):
Completed: 2
Run the following commands to verify:
velero restore get
NAME BACKUP STATUS ERRORS WARNINGS CREATED SELECTOR
guestbook-pv-backup-20200723161841 guestbook-pv-backup Completed 0 0 2020-07-23 16:18:41 -0700 PDT <none>
kubectl get ns
NAME STATUS AGE
default Active 16d
guestbook-pv Active 76s
kube-node-lease Active 16d
kube-public Active 16d
kube-system Active 16d
pks-system Active 16d
velero Active 2d2h
kubectl get all -n guestbook-pv
NAME READY STATUS RESTARTS AGE
pod/frontend-6cb7f8bd65-9cpdc 1/1 Running 0 2m4s
pod/frontend-6cb7f8bd65-h2pnb 1/1 Running 0 2m4s
pod/frontend-6cb7f8bd65-kwlpr 1/1 Running 0 2m4s
pod/frontend-6cb7f8bd65-snwl4 1/1 Running 0 2m4s
pod/redis-leader-64fb8775bf-kbs6s 1/1 Running 0 2m4s
pod/redis-follower-779b6d8f79-5dphr 1/1 Running 0 2m4s
NAME TYPE CLUSTER-IP EXTERNAL-IP PORT(S) AGE
service/frontend LoadBalancer 10.100.200.144 10.199.41.16 80:30038/TCP 2m4s
service/redis-leader ClusterIP 10.100.200.156 <none> 6379/TCP 2m4s
service/redis-follower ClusterIP 10.100.200.231 <none> 6379/TCP 2m4s
NAME READY UP-TO-DATE AVAILABLE AGE
deployment.apps/frontend 4/4 4 4 2m4s
deployment.apps/redis-leader 1/1 1 1 2m4s
deployment.apps/redis-follower 1/1 1 1 2m4s
NAME DESIRED CURRENT READY AGE
replicaset.apps/frontend-6cb7f8bd65 4 4 4 2m4s
replicaset.apps/redis-leader-64fb8775bf 1 1 1 2m4s
replicaset.apps/redis-follower-779b6d8f79 1 1 1 2m4s
kubectl get pvc,pv -n guestbook-pv
NAME STATUS VOLUME CAPACITY ACCESS MODES STORAGECLASS AGE
persistentvolumeclaim/redis-leader-claim Bound pvc-a2f6e6d4-42db-4fb8-a198-5379a2552509 2Gi RWO thin-disk 2m40s
persistentvolumeclaim/redis-follower-claim Bound pvc-55591938-921f-452a-b418-2cc680c0560b 2Gi RWO thin-disk 2m40s
NAME CAPACITY ACCESS MODES RECLAIM POLICY STATUS CLAIM STORAGECLASS REASON AGE
persistentvolume/pvc-55591938-921f-452a-b418-2cc680c0560b 2Gi RWO Delete Bound guestbook-pv/redis-follower-claim thin-disk 2m40s
persistentvolume/pvc-a2f6e6d4-42db-4fb8-a198-5379a2552509 2Gi RWO Delete Bound guestbook-pv/redis-leader-claim thin-disk 2m40s
Access the Guestbook app at http://10.199.41.16/.
