Back up Data to GCS Using BR

This document describes how to back up the data of a TiDB cluster in Kubernetes to Google Cloud Storage (GCS). BR is used to get the backup of the TiDB cluster, and then the backup data is sent to GCS.

The backup method described in this document is implemented using Custom Resource Definition (CRD) in TiDB Operator v1.1 or later versions.

Ad-hoc backup

Ad-hoc backup supports both full backup and incremental backup. It describes the backup by creating a Backup Custom Resource (CR) object. TiDB Operator performs the specific backup operation based on this Backup object. If an error occurs during the backup process, TiDB Operator does not retry, and you need to handle this error manually.

This document provides examples in which the data of the demo1 TiDB cluster in the test1 Kubernetes namespace is backed up to GCS.

Prerequisites for ad-hoc backup

1. Download backup-rbac.yaml, and execute the following command to create the role-based access control (RBAC) resources in the test1 namespace:

   kubectl apply -f backup-rbac.yaml -n test1
   

2. Grant permissions to the remote storage.

   Refer to GCS account permissions.

3. Create the backup-demo1-tidb-secret secret which stores the root account and password needed to access the TiDB cluster:

   kubectl create secret generic backup-demo1-tidb-secret --from-literal=password=<password> --namespace=test1
   

Required database account privileges

• The SELECT and UPDATE privileges of the mysql.tidb table: Before and after the backup, the Backup CR needs a database account with these privileges to adjust the GC time.

Process of ad-hoc backup

1. Create the Backup CR, and back up cluster data to GCS as described below:

   kubectl apply -f backup-gcs.yaml
   

   The content of backup-gcs.yaml is as follows:

   ---
   apiVersion: pingcap.com/v1alpha1
   kind: Backup
   metadata:
     name: demo1-backup-gcs
     namespace: test1
   spec:
     # backupType: full
     # Only needed for TiDB Operator < v1.1.10 or TiDB < v4.0.8
     from:
       host: ${tidb-host}
       port: ${tidb-port}
       user: ${tidb-user}
       secretName: backup-demo1-tidb-secret
     br:
       cluster: demo1
       clusterNamespace: test1
       # logLevel: info
       # statusAddr: ${status-addr}
       # concurrency: 4
       # rateLimit: 0
       # checksum: true
       # sendCredToTikv: true
       # options:
       # - --lastbackupts=420134118382108673
     gcs:
       projectId: ${project_id}
       secretName: gcs-secret
       bucket: ${bucket}
       prefix: ${prefix}
       # location: us-east1
       # storageClass: STANDARD_IA
       # objectAcl: private
   

   In the example above, some parameters in spec.br can be ignored, such as logLevel, statusAddr, concurrency, rateLimit, checksum, timeAgo, and sendCredToTikv. For more information about BR configuration, refer to BR fields.

   Since TiDB Operator v1.1.6, if you want to back up data incrementally, you only need to specify the last backup timestamp --lastbackupts in spec.br.options. For the limitations of incremental backup, refer to Use BR to Back up and Restore Data.

   The example above backs up all data in the TiDB cluster to GCS. Some parameters in spec.gcs can be ignored, such as location, objectAcl, and storageClass. For more information about GCS configuration, refer to GCS fields.

   For more information about the Backup CR fields, refer to Backup CR fields.

2. After creating the Backup CR, use the following command to check the backup status:

   kubectl get bk -n test1 -owide
   

Backup CR examples

---
apiVersion: pingcap.com/v1alpha1
kind: Backup
metadata:
  name: demo1-backup-gcs
  namespace: test1
spec:
  # backupType: full
  # Only needed for TiDB Operator < v1.1.10 or TiDB < v4.0.8
  from:
    host: ${tidb-host}
    port: ${tidb-port}
    user: ${tidb-user}
    secretName: backup-demo1-tidb-secret
  br:
    cluster: demo1
    clusterNamespace: test1
  gcs:
    projectId: ${project_id}
    secretName: gcs-secret
    bucket: ${bucket}
    prefix: ${prefix}
    # location: us-east1
    # storageClass: STANDARD_IA
    # objectAcl: private

---
apiVersion: pingcap.com/v1alpha1
kind: Backup
metadata:
  name: demo1-backup-gcs
  namespace: test1
spec:
  # backupType: full
  # Only needed for TiDB Operator < v1.1.10 or TiDB < v4.0.8
  from:
    host: ${tidb-host}
    port: ${tidb-port}
    user: ${tidb-user}
    secretName: backup-demo1-tidb-secret
  tableFilter:
  - "db1.*"
  br:
    cluster: demo1
    clusterNamespace: test1
  gcs:
    projectId: ${project_id}
    secretName: gcs-secret
    bucket: ${bucket}
    prefix: ${prefix}
    # location: us-east1
    # storageClass: STANDARD_IA
    # objectAcl: private

---
apiVersion: pingcap.com/v1alpha1
kind: Backup
metadata:
  name: demo1-backup-gcs
  namespace: test1
spec:
  # backupType: full
  # Only needed for TiDB Operator < v1.1.10 or TiDB < v4.0.8
  from:
    host: ${tidb-host}
    port: ${tidb-port}
    user: ${tidb-user}
    secretName: backup-demo1-tidb-secret
  tableFilter:
  - "db1.table1"
  br:
    cluster: demo1
    clusterNamespace: test1
  gcs:
    projectId: ${project_id}
    secretName: gcs-secret
    bucket: ${bucket}
    prefix: ${prefix}
    # location: us-east1
    # storageClass: STANDARD_IA
    # objectAcl: private

---
apiVersion: pingcap.com/v1alpha1
kind: Backup
metadata:
  name: demo1-backup-gcs
  namespace: test1
spec:
  # backupType: full
  # Only needed for TiDB Operator < v1.1.10 or TiDB < v4.0.8
  from:
    host: ${tidb-host}
    port: ${tidb-port}
    user: ${tidb-user}
    secretName: backup-demo1-tidb-secret
  tableFilter:
  - "db1.table1"
  - "db1.table2"
  br:
    cluster: demo1
    clusterNamespace: test1
  gcs:
    projectId: ${project_id}
    secretName: gcs-secret
    bucket: ${bucket}
    prefix: ${prefix}
    # location: us-east1
    # storageClass: STANDARD_IA
    # objectAcl: private

Scheduled full backup

You can set a backup policy to perform scheduled backups of the TiDB cluster, and set a backup retention policy to avoid excessive backup items. A scheduled full backup is described by a custom BackupSchedule CR object. A full backup is triggered at each backup time point. Its underlying implementation is the ad-hoc full backup.

Prerequisites for scheduled full backup

The prerequisites for the scheduled full backup is the same with the prerequisites for ad-hoc backup.

Process of scheduled full backup

1. Create the BackupSchedule CR, and back up cluster data as described below:

   kubectl apply -f backup-schedule-gcs.yaml
   

   The content of backup-schedule-gcs.yaml is as follows:

   ---
   apiVersion: pingcap.com/v1alpha1
   kind: BackupSchedule
   metadata:
     name: demo1-backup-schedule-gcs
     namespace: test1
   spec:
     #maxBackups: 5
     #pause: true
     maxReservedTime: "3h"
     schedule: "*/2 * * * *"
     backupTemplate:
       # Clean outdated backup data based on maxBackups or maxReservedTime. If not configured, the default policy is Retain
       # cleanPolicy: Delete
       # Only needed for TiDB Operator < v1.1.10 or TiDB < v4.0.8
       from:
         host: ${tidb_host}
         port: ${tidb_port}
         user: ${tidb_user}
         secretName: backup-demo1-tidb-secret
       br:
         cluster: demo1
         clusterNamespace: test1
         # logLevel: info
         # statusAddr: ${status-addr}
         # concurrency: 4
         # rateLimit: 0
         # checksum: true
         # sendCredToTikv: true
       gcs:
         secretName: gcs-secret
         projectId: ${project_id}
         bucket: ${bucket}
         prefix: ${prefix}
         # location: us-east1
         # storageClass: STANDARD_IA
         # objectAcl: private
   

2. After creating the scheduled full backup, use the following command to check the backup status:

   kubectl get bks -n test1 -owide
   

   Use the following command to check all the backup items:

   kubectl get bk -l tidb.pingcap.com/backup-schedule=demo1-backup-schedule-gcs -n test1
   

From the example above, you can see that the backupSchedule configuration consists of two parts. One is the unique configuration of backupSchedule, and the other is backupTemplate.

backupTemplate specifies the configuration related to the cluster and remote storage, which is the same as the spec configuration of the Backup CR. For the unique configuration of backupSchedule, refer to BackupSchedule CR fields.

Delete the backup CR

Refer to Delete the Backup CR.

Troubleshooting

If you encounter any problem during the backup process, refer to Common Deployment Failures.