Backup and Restore Microsoft SQL Server database using KubeStash

KubeStash allows you to backup and restore Microsoft SQL Server databases. It supports backups for Microsoft SQL Server instances running in Standalone, and Availability Group configurations. KubeStash makes managing your Microsoft SQL Server backups and restorations more straightforward and efficient.

This guide will give you an overview how you can take backup and restore your Microsoft SQL Server databases using Kubestash.

Before You Begin

  • At first, you need to have a Kubernetes cluster, and the kubectl command-line tool must be configured to communicate with your cluster. If you do not already have a cluster, you can create one by using Minikube or Kind.
  • Install KubeDB in your cluster following the steps here.
  • Install KubeStash in your cluster following the steps here.
  • Install KubeStash kubectl plugin following the steps here.
  • If you are not familiar with how KubeStash backup and restore Microsoft SQL Server databases, please check the following guide here.

You should be familiar with the following KubeStash concepts:

To keep everything isolated, we are going to use a separate namespace called demo throughout this tutorial.

$ kubectl create ns demo
namespace/demo created

Note: YAML files used in this tutorial are stored in docs/guides/mssqlserver/backup/logical/examples directory of kubedb/docs repository.

Backup Microsoft SQL Server

KubeStash supports backups for Microsoft SQL Server instances across different configurations, including Standalone and Availability Group setups. In this demonstration, we’ll focus on a Microsoft SQL Server database using Standalone configuration. The backup and restore process is similar for Availability Group configuration.

This section will demonstrate how to backup a Microsoft SQL Server database. Here, we are going to deploy a Microsoft SQL Server database using KubeDB. Then, we are going to backup this database into a GCS bucket. Finally, we are going to restore the backup up data into another Microsoft SQL Server database.

Deploy Sample Microsoft SQL Server Database

By default, a KubeDB-managed Microsoft SQL Server instance run with TLS disabled. However, the .spec.tls field is mandatory and will be used during backup and restore operations.

Create Issuer/ClusterIssuer:

Now, we are going to create an example Issuer CR that will be used throughout the duration of this tutorial. Alternatively, you can follow this cert-manager tutorial to create your own Issuer.

By following the below steps, we are going to create our desired issuer,

  • Start off by generating our ca-certificates using openssl,
$ openssl req -x509 -nodes -days 365 -newkey rsa:2048 -keyout ./ca.key -out ./ca.crt -subj "/CN=mssqlserver/O=kubedb"
  • create a secret using the certificate files we have just generated,
$ kubectl create secret tls mssqlserver-ca --cert=ca.crt  --key=ca.key --namespace=demo 
secret/mssqlserver-ca created

Now, we are going to create an Issuer CR using the mssqlserver-ca secret that contains the ca-certificate we have just created. Below is the YAML of the Issuer cr that we are going to create,

apiVersion: cert-manager.io/v1
kind: Issuer
metadata:
 name: mssqlserver-ca-issuer
 namespace: demo
spec:
 ca:
   secretName: mssqlserver-ca

Let’s create the Issuer CR we have shown above,

$ kubectl apply -f https://github.com/kubedb/docs/raw/v2024.9.30/docs/guides/mssqlserver/backup/logical/examples/mssqlserver-ca-issuer.yaml
issuer.cert-manager.io/mssqlserver-ca-issuer.yaml created

Create MSSQLServer CR:

Below is the YAML of a sample MSSQLServer CR that we are going to create for this tutorial:

apiVersion: kubedb.com/v1alpha2
kind: MSSQLServer
metadata:
  name: sample-mssqlserver
  namespace: demo
spec:
  version: "2022-cu12"
  replicas: 1
  storageType: Durable
  tls:
    issuerRef:
      name: mssqlserver-ca-issuer
      kind: Issuer
      apiGroup: "cert-manager.io"
    clientTLS: false
  storage:
    accessModes:
      - ReadWriteOnce
    resources:
      requests:
        storage: 1Gi
  deletionPolicy: WipeOut

Create the above MSSQLServer CR,

$ kubectl apply -f https://github.com/kubedb/docs/raw/v2024.9.30/docs/guides/mssqlserver/backup/logical/examples/sample-mssqlserver.yaml
mssqlserver.kubedb.com/sample-mssqlserver created

KubeDB will deploy a Microsoft SQL Server database according to the above specification. It will also create the necessary Secrets and Services to access the database.

Let’s check if the database is ready to use,

$ kubectl get mssqlserver -n demo sample-mssqlserver
NAME                 VERSION     STATUS   AGE
sample-mssqlserver   2022-cu12   Ready    3m27

The database is Ready. Verify that KubeDB has created a Secret and a Service for this database using the following commands,

$ kubectl get secret -n demo
NAME                                    TYPE                       DATA   AGE
mssqlserver-ca                          kubernetes.io/tls          2      2d20h
sample-mssqlserver-auth                 kubernetes.io/basic-auth   2      3m44s
sample-mssqlserver-client-cert          kubernetes.io/tls          3      3m14s
sample-mssqlserver-server-cert          kubernetes.io/tls          3      3m14s

$ kubectl get service -n demo -l=app.kubernetes.io/instance=sample-mssqlserver
NAME                      TYPE        CLUSTER-IP     EXTERNAL-IP   PORT(S)    AGE
sample-mssqlserver        ClusterIP   10.96.165.94   <none>        1433/TCP   4m32s
sample-mssqlserver-pods   ClusterIP   None           <none>        1433/TCP   4m32s

Here, we have to use service sample-mssqlserver and secret sample-mssqlserver-auth to connect with the database. KubeDB creates an AppBinding CR that holds the necessary information to connect with the database.

Verify AppBinding:

Verify that the AppBinding has been created successfully using the following command,

$ kubectl get appbindings -n demo
NAME                 TYPE                     VERSION   AGE
sample-mssqlserver   kubedb.com/mssqlserver   2022      4m18s

Let’s check the YAML of the above AppBinding,

$ kubectl get appbindings -n demo sample-mssqlserver -o yaml
apiVersion: appcatalog.appscode.com/v1alpha1
kind: AppBinding
metadata:
  annotations:
    kubectl.kubernetes.io/last-applied-configuration: |
      {"apiVersion":"kubedb.com/v1alpha2","kind":"MSSQLServer","metadata":{"annotations":{},"name":"sample-mssqlserver","namespace":"demo"},"spec":{"deletionPolicy":"WipeOut","replicas":1,"storage":{"accessModes":["ReadWriteOnce"],"resources":{"requests":{"storage":"1Gi"}}},"storageType":"Durable","tls":{"clientTLS":false,"issuerRef":{"apiGroup":"cert-manager.io","kind":"Issuer","name":"mssqlserver-ca-issuer"}},"version":"2022-cu12"}}      
  creationTimestamp: "2024-09-20T09:09:38Z"
  generation: 1
  labels:
    app.kubernetes.io/component: database
    app.kubernetes.io/instance: sample-mssqlserver
    app.kubernetes.io/managed-by: kubedb.com
    app.kubernetes.io/name: mssqlservers.kubedb.com
  name: sample-mssqlserver
  namespace: demo
  ownerReferences:
  - apiVersion: kubedb.com/v1alpha2
    blockOwnerDeletion: true
    controller: true
    kind: MSSQLServer
    name: sample-mssqlserver
    uid: 212fef79-23fb-4f3a-aea9-564ce1362174
  resourceVersion: "277078"
  uid: 01955aa0-f68e-410c-b952-c8516ea24922
spec:
  appRef:
    apiGroup: kubedb.com
    kind: MSSQLServer
    name: sample-mssqlserver
    namespace: demo
  clientConfig:
    service:
      name: sample-mssqlserver
      path: /
      port: 1433
      scheme: tcp
    url: tcp(sample-mssqlserver.demo.svc:1433)/
  secret:
    name: sample-mssqlserver-auth
  type: kubedb.com/mssqlserver
  version: "2022"

KubeStash uses the AppBinding CR to connect with the target database. It requires the following two fields to set in AppBinding’s .spec section.

Here,

  • .spec.clientConfig.service.name specifies the name of the Service that connects to the database.
  • .spec.secret specifies the name of the Secret that holds necessary credentials to access the database.
  • .spec.type specifies the types of the app that this AppBinding is pointing to. KubeDB generated AppBinding follows the following format: <app group>/<app resource type>.

Insert Sample Data:

Now, we are going to exec into one of the database pod and create some sample data. At first, find out the database Pod using the following command,

$ kubectl get pods -n demo --selector="app.kubernetes.io/instance=sample-mssqlserver"
NAME                   READY   STATUS    RESTARTS   AGE
sample-mssqlserver-0   1/1     Running   0          4m44s

And copy the username and password of the sa user to access into mssqlserver shell.

$ kubectl get secret -n demo  sample-mssqlserver-auth -o jsonpath='{.data.username}'| base64 -d
sa⏎

$ kubectl get secret -n demo  sample-mssqlserver-auth -o jsonpath='{.data.password}'| base64 -d
kkvAFfl8sIxRO2i3⏎

Now, Lets exec into the Pod to enter into mssqlserver shell and create a database and a table,

$ kubectl exec -it -n demo sample-mssqlserver-0 -c mssql -- /opt/mssql-tools/bin/sqlcmd -S sample-mssqlserver -U sa -P "kkvAFfl8sIxRO2i3"
# list available databases
1> SELECT name from sys.databases;
2> GO
name                                                                                                                            
--------------------------------------------------------------------------------------------------------------------------------
master                                                                                                                          
tempdb                                                                                                                          
model                                                                                                                           
msdb                                                                                                                            
kubedb_system                                                                                                                   

(5 rows affected)

# create a database named "playground"
1> CREATE DATABASE playground;
2> GO

# verify that the "playground" database has been created
1> SELECT name from sys.databases;
2> GO
name                                                                                                                            
--------------------------------------------------------------------------------------------------------------------------------
master                                                                                                                          
tempdb                                                                                                                          
model                                                                                                                           
msdb                                                                                                                            
kubedb_system                                                                                                                   
playground                                                                                                                      

(6 rows affected)
                                                                                                               
# Now create a 'equipment' table and insert multiple rows of data
1> USE playground;
2> CREATE TABLE equipment (id INT NOT NULL IDENTITY(1,1) PRIMARY KEY, type NVARCHAR(50), quant INT, color NVARCHAR(25));
3> INSERT INTO equipment (type, quant, color) VALUES ('Swing', 10, 'Red'), ('Slide', 5, 'Blue'), ('Monkey Bars', 3, 'Yellow');
4> GO

Changed database context to 'playground'.
(3 rows affected)

# Verify that data hase been inserted successfully
1> SELECT * FROM equipment;
2> GO
id          type                                               quant       color                    
----------- -------------------------------------------------- ----------- -------------------------
          1 Swing                                                       10 Red                      
          2 Slide                                                        5 Blue                     
          3 Monkey Bars                                                  3 Yellow                   

(3 rows affected)

# exit from the pod
1> exit

Now, we are ready to backup the database.

Prepare Backend

We are going to store our backed up data into a GCS bucket. We have to create a Secret with necessary credentials and a BackupStorage CR to use this backend. If you want to use a different backend, please read the respective backend configuration doc from here.

Create Secret:

Let’s create a secret called gcs-secret with access credentials to our desired GCS bucket,

$ echo -n '<your-project-id>' > GOOGLE_PROJECT_ID
$ cat /path/to/downloaded-sa-key.json > GOOGLE_SERVICE_ACCOUNT_JSON_KEY
$ kubectl create secret generic -n demo gcs-secret \
    --from-file=./GOOGLE_PROJECT_ID \
    --from-file=./GOOGLE_SERVICE_ACCOUNT_JSON_KEY
secret/gcs-secret created

Create BackupStorage:

Now, create a BackupStorage using this secret. Below is the YAML of BackupStorage CR we are going to create,

apiVersion: storage.kubestash.com/v1alpha1
kind: BackupStorage
metadata:
  name: gcs-storage
  namespace: demo
spec:
  storage:
    provider: gcs
    gcs:
      bucket: kubestash-qa
      prefix: demo
      secretName: gcs-secret
  usagePolicy:
    allowedNamespaces:
      from: All
  default: true
  deletionPolicy: Delete

Let’s create the BackupStorage we have shown above,

$ kubectl apply -f https://github.com/kubedb/docs/raw/v2024.9.30/docs/guides/mssqlserver/backup/logical/examples/backupstorage.yaml
backupstorage.storage.kubestash.com/gcs-storage created

Now, we are ready to backup our database to our desired backend.

Create RetentionPolicy:

Now, let’s create a RetentionPolicy to specify how the old Snapshots should be cleaned up.

Below is the YAML of the RetentionPolicy object that we are going to create,

apiVersion: storage.kubestash.com/v1alpha1
kind: RetentionPolicy
metadata:
  name: demo-retention
  namespace: demo
spec:
  default: true
  failedSnapshots:
    last: 2
  maxRetentionPeriod: 2mo
  successfulSnapshots:
    last: 5
  usagePolicy:
    allowedNamespaces:
      from: All

Let’s create the above RetentionPolicy,

$ kubectl apply -f https://github.com/kubedb/docs/raw/v2024.9.30/docs/guides/mssqlserver/backup/logical/examples/retentionpolicy.yaml
retentionpolicy.storage.kubestash.com/demo-retention created

Backup

We have to create a BackupConfiguration targeting respective sample-mssqlserver Microsoft SQL Server database. Then, KubeStash will create a CronJob for each session to take periodic backup of that database.

Below is the YAML for BackupConfiguration CR to backup the sample-mssqlserver Microsoft SQL Server database that we have deployed earlier,

apiVersion: core.kubestash.com/v1alpha1
kind: BackupConfiguration
metadata:
  name: sample-mssqlserver-backup
  namespace: demo
spec:
  target:
    apiGroup: kubedb.com
    kind: MSSQLServer
    namespace: demo
    name: sample-mssqlserver
  backends:
    - name: gcs-backend
      storageRef:
        namespace: demo
        name: gcs-storage
      retentionPolicy:
        name: demo-retention
        namespace: demo
  sessions:
    - name: frequent-backup
      scheduler:
        schedule: "*/5 * * * *"
        jobTemplate:
          backoffLimit: 1
      repositories:
        - name: gcs-mssqlserver-repo
          backend: gcs-backend
          directory: /mssqlserver
      addon:
        name: mssqlserver-addon
        jobTemplate:
          spec:
            securityContext:
              runAsUser: 0
        tasks:
          - name: logical-backup
  • .spec.sessions[*].schedule specifies that we want to backup the database at 5 minutes interval.
  • .spec.target refers to the targeted sample-mssqlserver Microsoft SQL Server database that we created earlier.

KubeStash utilizes Wal-G to perform logical backups of Microsoft SQL Server databases. Since Wal-G operates with root user privileges, it’s necessary to configure our backup job to run as a root user by specifying runAsUser: 0 in the spec.sessions[*].addon.jobTemplate.spec.securityContext section.

Let’s create the BackupConfiguration CR that we have shown above,

$ kubectl apply -f https://github.com/kubedb/docs/raw/v2024.9.30/docs/guides/mssqlserver/logical/examples/backupconfiguration.yaml
backupconfiguration.core.kubestash.com/sample-mssqlserver-backup created

Verify Backup Setup Successful

If everything goes well, the phase of the BackupConfiguration should be Ready. The Ready phase indicates that the backup setup is successful. Let’s verify the Phase of the BackupConfiguration,

$ kubectl get backupconfiguration -n demo
NAME                        PHASE   PAUSED   AGE
sample-mssqlserver-backup   Ready            2m50s

Additionally, we can verify that the Repository specified in the BackupConfiguration has been created using the following command,

$ kubectl get repo -n demo
NAME                     INTEGRITY   SNAPSHOT-COUNT   SIZE     PHASE   LAST-SUCCESSFUL-BACKUP   AGE
gcs-mssqlserver-repo                 0                0 B      Ready                            3m

KubeStash keeps the backup for Repository YAMLs. If we navigate to the GCS bucket, we will see the Repository YAML stored in the demo/mssqlserver directory.

Verify CronJob:

It will also create a CronJob with the schedule specified in spec.sessions[*].scheduler.schedule field of BackupConfiguration CR.

Verify that the CronJob has been created using the following command,

$ kubectl get cronjob -n demo
NAME                                                SCHEDULE      SUSPEND   ACTIVE   LAST SCHEDULE   AGE
trigger-sample-mssqlserver-backup-frequent-backup   */5 * * * *   False     0        4m52s           15m

Verify BackupSession:

KubeStash triggers an instant backup as soon as the BackupConfiguration is ready. After that, backups are scheduled according to the specified schedule.

$ kubectl get backupsession -n demo -w
NAME                                                   INVOKER-TYPE          INVOKER-NAME                 PHASE       DURATION   AGE
sample-mssqlserver-backup-frequent-backup-1725449400   BackupConfiguration   sample-mssqlserver-backup    Succeeded              7m22s

We can see from the above output that the backup session has succeeded. Now, we are going to verify whether the backed up data has been stored in the backend.

Verify Backup:

Once a backup is complete, KubeStash will update the respective Repository CR to reflect the backup. Check that the repository gcs-mssqlserver-repo has been updated by the following command,

$ kubectl get repository -n demo gcs-mssqlserver-repo
NAME                          INTEGRITY   SNAPSHOT-COUNT   SIZE    PHASE   LAST-SUCCESSFUL-BACKUP   AGE
gcs-mssqlserver-repo          true        1                806 B   Ready   8m27s                    9m18s

At this moment we have one Snapshot. Run the following command to check the respective Snapshot which represents the state of a backup run for an application.

$ kubectl get snapshots -n demo -l=kubestash.com/repo-name=gcs-mssqlserver-repo
NAME                                                              REPOSITORY             SESSION           SNAPSHOT-TIME          DELETION-POLICY   PHASE       AGE
gcs-mssqlserver-repo-sample-mssqckup-frequent-backup-1725449400   gcs-mssqlserver-repo   frequent-backup   2024-01-23T13:10:54Z   Delete            Succeeded   16h

Note: KubeStash creates a Snapshot with the following labels:

  • kubestash.com/app-ref-kind: <target-kind>
  • kubestash.com/app-ref-name: <target-name>
  • kubestash.com/app-ref-namespace: <target-namespace>
  • kubestash.com/repo-name: <repository-name>

These labels can be used to watch only the Snapshots related to our target Database or Repository.

If we check the YAML of the Snapshot, we can find the information about the backed up components of the Database.

$ kubectl get snapshots -n demo gcs-mssqlserver-repo-sample-mssqckup-frequent-backup-1725449400 -oyaml
apiVersion: storage.kubestash.com/v1alpha1
kind: Snapshot
metadata:
  annotations:
    kubedb.com/db-version: "2022"
  creationTimestamp: "2024-09-20T11:25:00Z"
  finalizers:
  - kubestash.com/cleanup
  generation: 1
  labels:
    kubestash.com/app-ref-kind: MSSQLServer
    kubestash.com/app-ref-name: sample-mssqlserver
    kubestash.com/app-ref-namespace: demo
    kubestash.com/repo-name: gcs-mssqlserver-repo
  name: gcs-mssqlserver-repo-sample-mssqckup-frequent-backup-1725449400
  namespace: demo
  ownerReferences:
  - apiVersion: storage.kubestash.com/v1alpha1
    blockOwnerDeletion: true
    controller: true
    kind: Repository
    name: gcs-mssqlserver-repo
    uid: 5774142d-a81d-44d6-9459-20c16a0d7ade
  resourceVersion: "293781"
  uid: b84c608c-8da8-444a-8db4-1632d04736e3
spec:
  appRef:
    apiGroup: kubedb.com
    kind: MSSQLServer
    name: sample-mssqlserver
    namespace: demo
  backupSession: sample-mssqlserver-backup-frequent-backup-1725449400
  deletionPolicy: Delete
  repository: gcs-mssqlserver-repo
  session: frequent-backup
  snapshotID: 01J87JV7HTH2FW71RBCTM56QWQ
  type: FullBackup
  version: v1
status:
  components:
    dump:
      driver: WalG
      duration: 19.996377s
      path: repository/v1/frequent-backup/dump
      phase: Succeeded
      walGStats:
        databases:
        - playground
        id: base_20240920T112503Z
        startTime: "2024-09-20T11:25:03Z"
        stopTime: "2024-09-20T11:25:23Z"
  conditions:
  - lastTransitionTime: "2024-09-20T11:25:00Z"
    message: Recent snapshot list updated successfully
    reason: SuccessfullyUpdatedRecentSnapshotList
    status: "True"
    type: RecentSnapshotListUpdated
  - lastTransitionTime: "2024-09-20T11:25:26Z"
    message: Metadata uploaded to backend successfully
    reason: SuccessfullyUploadedSnapshotMetadata
    status: "True"
    type: SnapshotMetadataUploaded
  phase: Succeeded
  snapshotTime: "2024-09-20T11:25:00Z"
  totalComponents: 1

Now, if we navigate to the GCS bucket, we will see the backed up data stored in the demo/mssqlserver/repository/v1/frequent-backup/dump/basebackups_005 directory. KubeStash also keeps the backup for Snapshot YAMLs, which can be found in the demo/mssqlserver/snapshots directory.

Restore

In this section, we are going to restore the database from the backup we have taken in the previous section. We are going to deploy a new database and initialize it from the backup.

Now, we have to deploy the restored database similarly as we have deployed the original sample-mssqlserver database. However, this time there will be the following differences:

  • We are going to specify .spec.init.waitForInitialRestore field that tells KubeDB to wait for first restore to complete before marking this database is ready to use.

Below is the YAML for MSSQLServer CR we are going deploy to initialize from backup,

apiVersion: kubedb.com/v1alpha2
kind: MSSQLServer
metadata:
  name: restored-mssqlserver
  namespace: demo
spec:
  init:
    waitForInitialRestore: true
  version: "2022-cu12"
  replicas: 1
  storageType: Durable
  tls:
    issuerRef:
      name: mssqlserver-ca-issuer
      kind: Issuer
      apiGroup: "cert-manager.io"
    clientTLS: false
  storage:
    accessModes:
      - ReadWriteOnce
    resources:
      requests:
        storage: 1Gi
  deletionPolicy: WipeOut

Let’s create the above database,

$ kubectl apply -f https://github.com/kubedb/docs/raw/v2024.9.30/docs/guides/mssqlserver/backup/logical/examples/restored-mssqlserver.yaml
mssqlserver.kubedb.com/restored-mssqlserver created

If you check the database status, you will see it is stuck in Provisioning state.

$ kubectl get mssqlserver -n demo restored-mssqlserver
NAME                   VERSION     STATUS          AGE
restored-mssqlserver   2022-cu12   Provisioning    7m37

Create RestoreSession:

Now, we need to create a RestoreSession CR pointing to targeted Microsoft SQL Server database.

Below, is the contents of YAML file of the RestoreSession object that we are going to create to restore backed up data into the newly created Microsoft SQL Server database named restored-mssqlserver.

apiVersion: core.kubestash.com/v1alpha1
kind: RestoreSession
metadata:
  name: sample-mssqlserver-restore
  namespace: demo
spec:
  target:
    apiGroup: kubedb.com
    kind: MSSQLServer
    namespace: demo
    name: restored-mssqlserver
  dataSource:
    repository: gcs-mssqlserver-repo
    snapshot: latest
  addon:
    name: mssqlserver-addon
    jobTemplate:
      spec:
        securityContext:
          runAsUser: 0
    tasks:
      - name: logical-backup-restore

Here,

  • .spec.target refers to the newly created restored-mssqlserver Microsoft SQL Server object to where we want to restore backup data.
  • .spec.dataSource.repository specifies the Repository object that holds the backed up data.
  • .spec.dataSource.snapshot specifies to restore from latest Snapshot.

KubeStash utilizes Wal-G to perform logical restores of Microsoft SQL Server databases. Since Wal-G operates with root user privileges, it’s necessary to configure our restore job to run as a root user by specifying runAsUser: 0 in the .spe.addon.jobTemplate.spec.securityContext section.

Let’s create the RestoreSession CRD object we have shown above,

$ kubectl apply -f https://github.com/kubedb/docs/raw/v2024.9.30/docs/guides/mssqlserver/backup/logical/examples/restoresession.yaml
restoresession.core.kubestash.com/sample-mssqlserver-restore created

Once, you have created the RestoreSession object, KubeStash will create restore Job. Run the following command to watch the phase of the RestoreSession object,

$ watch kubectl get restoresession -n demo
Every 2.0s: kubectl get restores... AppsCode-PC-03: Wed Aug 21 10:44:05 2024
NAME                      REPOSITORY            FAILURE-POLICY    PHASE       DURATION   AGE
sample-mssql-restore      gcs-mssqlserver-repo                    Succeeded   12s        8m7s

The Succeeded phase means that the restore process has been completed successfully.

Verify Restored Data:

In this section, we are going to verify whether the desired data has been restored successfully. We are going to connect to the database server and check whether the database and the table we created earlier in the original database are restored.

At first, check if the database has gone into Ready state by the following command,

$ kubectl get mssqlserver -n demo restored-mssqlserver
NAME                   VERSION     STATUS   AGE
restored-mssqlserver   2022-cu12   Ready    13m

Now, find out the database Pod using the following command,

$ kubectl get pods -n demo --selector="app.kubernetes.io/instance=restored-mssqlserver"
NAME                         READY   STATUS      RESTARTS   AGE
restored-mssqlserver-0       1/1     Running     0          16m

And copy the username and password of the sa user to access into mssqlserver shell.

$ kubectl get secret -n demo  restored-mssqlserver-auth -o jsonpath='{.data.username}'| base64 -d
sa⏎

$ kubectl get secret -n demo  restored-mssqlserver-auth -o jsonpath='{.data.password}'| base64 -d
Ag9qi8zQiFew0xHo⏎

Now, Lets exec into the Pod to enter into mssqlserver shell and verify restored data,

$ kubectl exec -it -n demo restored-mssqlserver-0 -c mssql -- /opt/mssql-tools/bin/sqlcmd -S restored-mssqlserver -U sa -P "Ag9qi8zQiFew0xHo"
1> SELECT name from sys.databases;
2> GO
name                                                                                                                            
--------------------------------------------------------------------------------------------------------------------------------
master                                                                                                                          
tempdb                                                                                                                          
model                                                                                                                           
msdb                                                                                                                            
kubedb_system                                                                                                                   
playground                                                                                                                      

(6 rows affected)

1> USE playground;
2> SELECT name from sys.tables;
3> GO
Changed database context to 'playground'.
name                                                                                                                            
--------------------------------------------------------------------------------------------------------------------------------
equipment 

(1 rows affected)

1> SELECT * FROM equipment;
2> GO
id          type                                               quant       color                    
----------- -------------------------------------------------- ----------- -------------------------
          1 Swing                                                       10 Red                      
          2 Slide                                                        5 Blue                     
          3 Monkey Bars                                                  3 Yellow                   

(3 rows affected)
> exit

So, from the above output, we can see that the playground database and the equipment table we have created earlier in the original database and now, they are restored successfully.

Cleanup

To cleanup the Kubernetes resources created by this tutorial, run:

kubectl delete backupconfigurations.core.kubestash.com  -n demo sample-mssqlserver-backup
kubectl delete restoresessions.core.kubestash.com -n demo sample-mssqlserver-restore
kubectl delete retentionpolicies.storage.kubestash.com -n demo demo-retention
kubectl delete backupstorage -n demo gcs-storage
kubectl delete secret -n demo gcs-secret
kubectl delete secrets -n demo mssqlserver-ca
kubectl delete mssqlserver -n demo restored-mssqlserver
kubectl delete mssqlserver -n demo sample-mssqlserver
kubectl delete issuer -n demo mssqlserver-ca-issuer