Backing Up and Restoring VMware SQL with MySQL for Kubernetes Instances

This topic describes how to back up and restore VMware SQL with MySQL for Kubernetes.

Overview

VMware MySQL Operator allows you to generate on-demand backups, configure schedules for automated backups, and restore backups to new MySQL instances.

For uploading and retrieving backup artifacts, VMware MySQL Operator currently supports S3-compatible storage and Azure Blob Storage.

For backing up and restoring, VMware MySQL Operator uses four Custom Resource Definitions (CRDs):

• MySQLBackup: References a MySQL backup artifact that exists in an external blobstore such as S3 or Minio. A new MySQLBackup resource is created every time an on-demand or scheduled backup is generated.

• MySQLBackupLocation: References an external blobstore and credentials necessary to access the blobstore.

• MySQLBackupSchedule: Represents a CronJob schedule on which to perform backups.

• MySQLRestore: References an instance of a restore that was performed. A new MySQLRestore resource is created every time a restore is performed.

For detailed information about the CRDs, see Controllers and Custom Resource Definitions (CRDs) in Architecture.

Note: The procedures in this topic require the VMware SQL with MySQL for Kubernetes deployment templates. If you have not yet downloaded the deployment templates, see Download the Deployment Templates in Creating and Deleting MySQL Instances.

About Synchronization of Backups with the External Blobstore

VMware MySQL Operator syncs MySQLBackup resources in a Kubernetes cluster with the contents of the external blobstore. The external blobstore is treated as the source of truth. This means that, if a MySQLBackup resource is deleted on the Kubernetes cluster, but the associated backup artifact still exists in the external blobstore, VMware MySQL Operator re-creates the MySQLBackup resource to match the contents of the external blobstore.

Back Up VMware MySQL Operator Data

Performing backups for VMware MySQL Operator requires creating a MySQLBackupLocation resource that references an external blobstore. Both on-demand backups and scheduled backups use the MySQLBackupLocation to upload backup artifacts to the external blobstore.

Before starting the procedures for backing up a VMware MySQL Operator instance, ensure that you know the configuration details of your external blobstore and how often you want to perform scheduled backups.

Create a MySQLBackupLocation Resource

The MySQLBackupLocation Resource is used to configure the namespace with the location of the blobstore, and the credentials to access it. If your storage endpoint uses custom TLS certificates, provide your CA bundle in the MySQLBackupLocation Resource.

For details on the backup location CR and its properties, refer to Properties for the MySQLBackupLocation Resource, and Properties for the Secret.

To create a MySQLBackupLocation resource:

1. Find the backuplocation.yaml deployment template that you downloaded in the TGZ file from VMware Tanzu Network. For how to download deployment templates, see Download the Deployment Templates in Creating and Deleting MySQL Instances.

2. Create a copy of the backuplocation.yaml file and give it a unique name.

   For example:

   cp ~/Downloads/mysql-for-kubernetes-1.9.0/samples/backuplocation.yaml testbackuplocation.yaml
   

3. Edit the file with the configuration details of your external blobstore.

4. Create the MySQLBackupLocation resource in the same namespace as the MySQL instances that you want to back up by running:

   kubectl apply -f FILENAME -n DEVELOPMENT-NAMESPACE
   

   • Where is DEVELOPMENT-NAMESPACE is the namespace for the MySQL instance.
   • Where FILENAME is the name of the configuration file you created in Step 2 above.

   For example:

   kubectl apply -f testbackuplocation.yaml -n my-namespace
   

   mysqlbackuplocation.with.sql.tanzu.vmware.com/backuplocation-sample created
   secret/backuplocation-sample-creds configured
   

5. Verify that the MySQLBackupLocation has been created by running:

   kubectl get mysqlbackuplocation backuplocation-sample \
   -o jsonpath={.spec} -n DEVELOPMENT-NAMESPACE
   

   For example:

   kubectl get mysqlbackuplocation backuplocation-sample -o jsonpath={.spec} -n my-namespace
   

   {
     "storage": {
       "s3": {
         "bucket": "bucket-sample",
         "forcePathStyle": false,
         "region": "us-west-1",
         "secret": {
           "name": "backuplocation-sample-creds"
         }
       }
     }
   }
   

Create a MySQLBackupSchedule Resource

To set a schedule for automatic backups, create a MySQLBackupSchedule resource:

1. Find the backupschedule.yaml deployment template that you downloaded in the TGZ file from VMware Tanzu Network. For how to download deployment templates, see Download the Deployment Templates in Creating and Deleting MySQL Instances.

2. Create a copy of the backupschedule.yaml file and give it a unique name.

   For example:

   cp ~/Downloads/mysql-for-kubernetes-1.9.0/samples/backupschedule.yaml testbackupschedule.yaml
   

3. Edit the file with the name of the MySQLBackupLocation resource that you created in Create a MySQLBackupLocation Resource and the name of the MySQL instance you want scheduled backups of. For an explanation of the properties that you can set in this file, see Properties for the MySQLBackupSchedule Resource.

4. Create the MySQLBackupSchedule resource in the same namespace as the MySQLBackupLocation and MySQL instance that you referenced in the MySQLBackupSchedule YAML file.

   kubectl apply -f FILENAME -n DEVELOPMENT-NAMESPACE
   

   Where FILENAME is the name of the configuration file you created in Step 2 above.

   For example:

   kubectl apply -f testbackupschedule.yaml -n my-namespace
   

   mysqlbackupschedule.with.sql.tanzu.vmware.com/backupschedule-sample created
   

5. Verify that the MySQLBackupSchedule has been created by running:

   kubectl get mysqlbackupschedule mysqlbackupschedule-sample -o jsonpath={.spec} -n DEVELOPMENT-NAMESPACE
   

   For example:

   kubectl get mysqlbackupschedule mysqlbackupschedule-sample -o jsonpath={.spec} -n my-namespace
   {
     "backupTemplate": {
       "spec": {
         "instance": {
           "name": "demo-db"
         },
         "location": {
           "name": "demo-backuplocation"
         }
       }
     },
     "schedule": "@daily"
   }
   

   If you correctly configured both a MySQLBackupLocation resource and MySQLBackupSchedule resource for an existing MySQL instance, you see backups being generated and uploaded to the external blobstore.

Extending MySQLBackupSchedule to Collect Binary Logs for Better Recovery

Recovery Point Objective (RPO) refers to how much data loss your application can tolerate. The smaller the RPO, the less data loss involved during an outage.

To minimize RPO, restore transactions after a full backup. To accomplish this, configure MySQLBackupSchedule to save binary logs of the MySQL instance as full backups in the same blob store where the backups of the MySQL instance are stored.

To enable binary log collection, set the spec.binaryLogCollection fields (spec.binaryLogCollection.enabled, spec.binaryLogCollection.flushInterval, and spec.binaryLogCollection.resources) in the MySQLBackupSchedule. For more information, see MySQLBackupSchedule Property Reference.

For example, you can configure MySQLBackupSchedule to enable binary log collection every five minutes as follows:

binaryLogCollection:
  enabled: true
  flushInterval: 5m

To improve Recovery Time Objective (RTO), configure the flush interval to be shorter so that binary logs are flushed and uploaded to the blobstore more frequently. To review all the options, see the MySQLBackupSchedule Property Reference.

Note: If binary logs are purged or rotated before they can be collected, point-in-time recovery does not restore all the desired data successfully .

The binary logs are collected and uploaded to the blobstore in a separate Kubernetes deployment named <SCHEDULE>-binlog-collector where SCHEDULE is the name of the MySQLBackupSchedule.

To configure resources for the container that is collecting and uploading the binary logs, set the resource requirements with spec.binaryLogCollection.resources.

Name and Location for Backup Artifacts

MySQLBackup resources that are automatically generated as a result of a MySQLBackupSchedule are named SCHEDULE-NAME-TIMESTAMP.

By default, VMware MySQL Operator stores backup artifacts under the subfolder structure mysql-<instance-name>-<instance-uuid> / backups / yyyy / mm / dd /. You can configure a custom path for backups so that backup artifacts are stored under the subfolder structure CUSTOM-PATH / mysql-<instance-name>-<instance-uuid> / backups / yyyy / mm / dd.

Backup artifacts stored in the external blobstore are named DATETIME-RANDOM_STRING-backup.xb.

For example, a user has an instance called sample-instance with a UUID of bf5398d1-c0fb-4459-a024-559e9855a2cd. If a MySQLBackupSchedule name is mysqlbackupschedule-sample, the custom backup path is my-backups/, and a backup was taken on Thursday, December 10, 2020 at 8:51:03 PM GMT (timestamp 1607633463), then:

• The MySQLBackup resource on the Kubernetes cluster is named mysqlbackupschedule-sample-1607633463
• The backup artifact in the external blobstore is named 20201210T205103-kzw54l-backup.xb
• The path to the artifact is my-backups/mysql-sample-instance-bf5398d1-c0fb-4459-a024-559e9855a2cd/backups/2020/12/10/.

If you enable binary log collection, then binary logs are stored in a subfolder structure CUSTOM-PATH / mysql-<instance-name>-<instance-uuid> / binlogs.

The binary logs are named as binlog_<timestamp>, where timestamp is the Unix time of the first transaction in the binary log. The Global Transaction Identifier (GTID) of the transactions associated with this binary log are stored in a blob named gtid_binlog_<timestamp>.

For example, if you use the same sample-instance, if the MySQL database has flushed logs, and if there is a binary log whose first transaction occurs with Unix timestamp 1607633463, then: * The name of the binary log is binlog_1607633463 * The path to the binary log is my-backups/mysql-sample-instance-bf5398d1-c0fb-4459-a024-559e9855a2cd/binlogs/binlog_1607633463. * The path to the GTID blob is my-backups/mysql-sample-instance-bf5398d1-c0fb-4459-a024-559e9855a2cd/binlogs/gtid_binlog_1607633463.

Perform an On-Demand Backup

In addition to scheduled backups, you can take individual backups whenever you want.

Prerequisite: A MySQLBackupLocation resource that represents the external blobstore to which you upload the generated backup artifact. To configure the MySQLBackupLocation resource, see Create a MySQLBackupLocation Resource above.

To take a backup:

1. Find the backup.yaml deployment template that you downloaded in the TGZ file from VMware Tanzu Network. For how to download deployment templates, see Download the Deployment Templates in Creating and Deleting MySQL Instances.

2. Create a copy of the backup.yaml file and give it a unique name.

   For example:

   cp ~/Downloads/mysql-for-kubernetes-1.9.0/samples/backup.yaml testbackup.yaml
   

3. Edit the file. For an explanation of the properties that you can set for the MySQLBackup resource, see Properties for the MySQLBackup Resource.

4. Trigger the backup by creating the MySQLBackup resource in the same namespace as the instance by running:

   kubectl apply -f FILENAME -n DEVELOPMENT-NAMESPACE
   

   Where FILENAME is the name of the configuration file you created in Step 2 above.

   For example:

   kubectl apply -f testbackup.yaml -n my-namespace
   mysqlbackup.with.sql.tanzu.vmware.com/backup-sample created
   

5. Verify that a backup has been generated and track its progress by running:

   kubectl get mysqlbackup backup-sample -n DEVELOPMENT-NAMESPACE
   

   For example:

   kubectl get mysqlbackup backup-sample -n my-namespace
   

   NAME            STATUS      SOURCE INSTANCE   TIME STARTED           TIME COMPLETED
   backup-sample   Succeeded   mysql-sample      2020-12-01T21:49:26Z   2020-12-01T21:49:30Z
   

   For an explanation of what each column means, see List Existing MySQLBackup Resources below.

List Existing MySQLBackup Resources

You might want to list existing MySQLBackup resources for various reasons, for example:

• To select a backup to restore. For steps to restore a backup, see Restore.
• To see the last successful backup.
• To verify that scheduled backups are running as expected.
• To find old backups that need to be cleaned up. For steps to delete backups, see Delete Old Backup Artifacts.

To see a list of existing MySQLBackup resources:

1. List existing MySQLBackup resources by running:

   kubectl get mysqlbackup
   

   For example:

   kubectl get mysqlbackup
   NAME            STATUS   SOURCE INSTANCE   TIME STARTED   TIME COMPLETED
   backup-sample   Failed   mysql-sample
   

2. To understand the output, see the table below:

   Column Name	Meaning
   STATUS	Represents the current status of the backup. Allowed values are: Pending: The backup has been received but not scheduled on a MySQL Pod. Running: The backup is being generated and streamed to the external blobstore. Succeeded: The backup has completed successfully. Failed: The backup has failed to complete. To troubleshoot a failed backup, see Troubleshoot Backup and Restore below.
   SOURCE INSTANCE	The MySQL instance the backup was taken from.
   TIME STARTED	The time that the backup process started.
   TIME COMPLETED	The time that the backup process finished. If the backup fails, this value is empty.

Delete Old Backup Artifacts

VMware SQL with MySQL for Kubernetes does not natively support retention policies for backup artifacts. You can configure retention policies on your external blobstore. If you do, you must also delete the associated MySQLBackup resources in the Kubernetes cluster, because those are not automatically deleted by VMware SQL with MySQL for Kubernetes.

To delete a backup:

1. Delete the backup in the external blobstore.

2. On your Kubernetes cluster, delete the MySQLBackup resource by running:

   kubectl delete mysqlbackup BACKUP-NAME -n DEVELOPMENT-NAMESPACE
   

   For example:

   kubectl delete mysqlbackup backup-sample -n my-namespace
   

Restore

This section discusses three kinds of restores:

• Restore from a Backup
• Restore a Backup to a Different Namespace or Kubernetes Cluster
• Restore to a point in time using binary logs

Restore from a Backup

MySQLRestores always restores to a new MySQL instance to avoid overwriting any data on an existing MySQL instance. When the restore is triggered, it automatically creates the new MySQL instance.

VMware MySQL Operator does not allow you to restore a backup to an existing MySQL instance. Although you can perform this manually by copying the MySQL data from the backup artifact onto an existing MySQL instance, VMware strongly discourages you from doing this because you might overwrite existing data on the MySQL instance.

Prerequisites

Before you restore from a backup, you must have:

• An existing MySQLBackup in your current namespace. To select an existing MySQLBackup to restore, see List Existing MySQLBackup Resources.
• A MySQLBackupLocation that represents the bucket where the existing backup artifact is stored. See Create a MySQLBackupLocation Resource above.

Procedure

To restore from a backup:

1. Find the restore.yaml deployment template that you downloaded in the TGZ file from VMware Tanzu Network. For how to download deployment templates, see Download the Deployment Templates in Creating and Deleting MySQL Instances.

2. Create a copy of the restore.yaml file and give it a unique name.

   For example:

   cp ~/Downloads/mysql-for-kubernetes-1.9.0/samples/restore.yaml testrestore.yaml
   

3. Edit the file. For information about the properties that you can set for the MySQLRestore resource, see Property Reference for Backup and Restore.

   To restore from an HA instance to a non-HA instance, edit the testrestore.yaml and amend the spec.instanceTemplate.spec.highAvailability field to false. For example:

   ---
   apiVersion: with.sql.tanzu.vmware.com/v1
   kind: MySQLRestore
   metadata:
     name: restore-sample
   spec:
     backup:
        name: backup-sample
     instanceTemplate:
        metadata:
          name: mysql-sample
        spec:
          storageSize: 1Gi
          imagePullSecretName: tanzu-image-registry
          highAvailability:
            enabled: false
   

4. Trigger the restore by creating the MySQLRestore resource in the same namespace as the MySQLBackup and MySQLBackupLocation by running:

   kubectl apply -f FILENAME -n DEVELOPMENT-NAMESPACE
   

   Where FILENAME is the name of the configuration file you created in Step 2 above.

   For example:

   kubectl apply -f testrestore.yaml -n my-namespace
   

   mysqlrestore.with.sql.tanzu.vmware.com/restore-sample created
   

5. Verify that a restore has been triggered and track the progress of your restore by running:

   kubectl get mysqlrestore restore-sample -n DEVELOPMENT-NAMESPACE
   

   For example:

   kubectl get mysqlrestore restore-sample -n my-namespace
   

   NAME             STATUS      SOURCE BACKUP   TARGET INSTANCE   TIME STARTED           TIME COMPLETED
   restore-sample   Succeeded   backup-sample   mysql-sample      2020-12-01T21:52:30Z   2020-12-01T21:53:09Z
   

6. To understand the output, see the table below:

   Column Name	Meaning
   STATUS	Represents the current status of the restore process. Allowed values are: Pending: The restore has been received but not yet scheduled on a MySQL Pod. Running: The restore is in progress. Succeeded: The restore has completed successfully. Failed: The restore failed. To troubleshoot, see Troubleshoot Backup and Restore below.
   SOURCE BACKUP	The name of the backup being restored.
   TARGET INSTANCE	The name of the new MySQL instance to be restored with the backup contents.
   TIME STARTED	The time that the restore process started.
   TIME COMPLETED	The time that the restore process finished. If the restore fails, this value is empty.

Restoring a Backup to a Different Namespace or Kubernetes Cluster

If you want to restore a backup to a different namespace or a different Kubernetes cluster, create a MySQLBackupLocation in the target namespace or Kubernetes cluster. Then, VMware MySQL Operator automatically creates MySQLBackup resources for the backup artifacts in the external blobstore.

To restore to a different namespace or Kubernetes cluster, you create a BackupLocation in the target namespace:

1. Target the destination Kubernetes cluster or namespace.

2. Create a MySQLBackupLocation resource that contains the backup artifact to restore. For how to do this, see Create a MySQLBackupLocation Resource.

3. Confirm that the MySQLBackup artifact to restore is included in the list by running:

   kubectl get mysqlbackup
   

   For example:

   kubectl get mysqlbackup
   

   NAME            STATUS      SOURCE INSTANCE   TIME STARTED           TIME COMPLETED
   sample-backup   Succeeded   mysql-sample      2020-12-01T21:49:26Z   2020-12-01T21:49:30Z
   

4. Trigger a restore by following steps in Restore from a Backup.

Restoring to a Point in Time Using Binary Logs

To restore a backup along with binary logs, you must first enable binary log collection. Review the documentation to enable binary log connection.

To speed up application recovery, you can reduce Recovery Time Objective (RTO). Thereby, you can restore the MySQL instance to a point in time first by using the full backup right before the time of recovery and recover the binary logs as well.

You can use the field spec.pitr.type in a MySQLRestore object and restore backups to a point in time using binary logs in two ways: * Timestamp: The recovery process restores the binary logs until the required timestamp is reached. * Latest: The recovery process restores all the binary logs available in the blobstore.

There are two ways to provide the backup artifact: * By providing the name of the MySQLBackup object. * By providing the name and UID of the MySQL object and by allowing the operator to find the latest MySQLBackup object associated with the MySQL instance. If a recovery timestamp is provided, the operator looks for the latest MySQLBackup before the timestamp.

To review all the options, see the MySQLRestore Property Reference.

Some examples:

• If the most recent backup named backup-sample is of two days before and you wish to create a new MySQL instance with all the latest data from a source instance, then the you can create a MySQLRestore as follows:

apiVersion: with.sql.tanzu.vmware.com/v1
kind: MySQLRestore
metadata:
  name: restore-sample
spec:
  backup:
    name: backup-sample
  instanceTemplate:
    metadata:
      name: new-mysql-sample
    spec:
      imagePullSecretName: tanzu-image-registry
  pitr:
    type: Latest

• If the most recent backup named backup-sample is of two days before and there is a specific transaction that is undesired, then you must identify the timestamp of the transaction and provide it in the MySQLRestore as follows:

apiVersion: with.sql.tanzu.vmware.com/v1
kind: MySQLRestore
metadata:
  name: restore-sample
spec:
  backup:
    name: backup-sample
  instanceTemplate:
    metadata:
      name: new-mysql-sample
    spec:
      imagePullSecretName: tanzu-image-registry
  pitr:
    type: Timestamp
    timestamp: "2023-05-25T19:22:15Z"

To avoid the work of finding the latest MySQLBackup before a specific timestamp, you can specify the identity of the source MySQL instance with spec.searchForBackup to allow the operator to find the appropriate MySQLBackup as follows:

apiVersion: with.sql.tanzu.vmware.com/v1
kind: MySQLRestore
metadata:
  name: restore-sample
spec:
  searchForBackup:
    instanceName: mysql-sample
    instanceUid: 4e1677b5-9b9a-4b2a-bd90-9799441a145f
  instanceTemplate:
    metadata:
      name: new-mysql-sample
    spec:
      imagePullSecretName: tanzu-image-registry
  pitr:
    type: Timestamp
    timestamp: "2023-05-25T19:22:15Z"

Troubleshoot Backup and Restore

Basic troubleshooting begins with reviewing the status for the resource and reading the messages associated with the resource events.

To troubleshoot problems with backup and restore:

1. Detect issues by monitoring the STATUS column of any MySQL custom resource. If the status is Failed or is stuck in Pending, Scheduled, or Running, then one of the following might be the problem:

   • Misconfiguration
   • Problem with the external blobstore
   • Issues with the MySQL Operator

   In this example, the kubectl get command outputs a Failed status:

   kubectl get mysqlbackup backup-sample
   

   NAME            STATUS   SOURCE INSTANCE   TIME STARTED   TIME COMPLETED
   backup-sample   Failed   mysql-sample
   

2. Diagnose the issue by inspecting the Kubernetes events for the resource, for example:

   kubectl get events --field-selector involvedObject.name=backup-sample
   

   LAST SEEN   TYPE      REASON   OBJECT                      MESSAGE
   2m43s       Warning   Failed   mysqlbackup/backup-sample   Secret "backuplocation-sample-creds" not found
   

3. Read the message in the MESSAGE column to understand why the failure occurred.
   
   

   In the example above, the backup-sample expected a Kubernetes secret called backuplocation-sample-creds to exist. Fix this problem by creating the backuplocation-sample-creds secret. The template for this secret is located in the backuplocation.yaml template.