Restore Data from S3-Compatible Storage Using BR

This document describes how to restore the TiDB cluster data backed up using TiDB Operator in Kubernetes.

The restore method described in this document is implemented based on CustomResourceDefinition (CRD) in TiDB Operator. For the underlying implementation, BR is used to restore the data. BR stands for Backup & Restore, which is a command-line tool for distributed backup and recovery of the TiDB cluster data.

Usage Scenarios

After backing up TiDB cluster data to Amazon S3 using BR, if you need to recover the backup SST (key-value pairs) files from Amazon S3 to a TiDB cluster, you can follow steps in this document to restore the data using BR.

Restore Data Using BR - 图1Note

  • BR is only applicable to TiDB v3.1 or later releases.
  • Data restored by BR cannot be replicated to a downstream cluster, because BR directly imports SST files to TiDB and the downstream cluster currently cannot access the upstream SST files.

This document provides an example about how to restore the backup data from the spec.s3.prefix folder of the spec.s3.bucket bucket on Amazon S3 to the demo2 TiDB cluster in the test2 namespace. The following are the detailed steps.

Step 1: Prepare the restore environment

Before restoring backup data on a S3-compatible storage to TiDB using BR, take the following steps to prepare the restore environment:

  1. Download backup-rbac.yaml, and execute the following command to create the role-based access control (RBAC) resources in the test2 namespace:

    1. kubectl apply -f backup-rbac.yaml -n test2

  2. Grant permissions to the remote storage.

    If the data to be restored is in Amazon S3, you can grant permissions in three methods. For more information, see AWS account permissions.

    If the data to be restored is in other S3-compatible storage (such as Ceph and MinIO), you can grant permissions by using AccessKey and SecretKey.

  3. For a TiDB version earlier than v4.0.8, you also need to complete the following preparation steps. For TiDB v4.0.8 or a later version, skip these preparation steps.

    1. Make sure that you have the SELECT and UPDATE privileges on the mysql.tidb table of the target database so that the Restore CR can adjust the GC time before and after the restore.

    2. Create the restore-demo2-tidb-secret secret to store the account and password to access the TiDB cluster:

      1. kubectl create secret generic restore-demo2-tidb-secret --from-literal=password=${password} --namespace=test2

Step 2: Restore the backup data to a TiDB cluster

Depending on which method you choose to grant permissions to the remote storage when preparing the restore environment, you can restore the data by doing one of the following:

  • Method 1: If you grant permissions by importing AccessKey and SecretKey, create the Restore CR to restore cluster data as described below:

    1. kubectl apply -f resotre-aws-s3.yaml

    The content of restore-aws-s3.yaml is as follows:

    1. ---
    2. apiVersion: pingcap.com/v1alpha1
    3. kind: Restore
    4. metadata:
    5.   name: demo2-restore-s3
    6.   namespace: test2
    7. spec:
    8.   br:
    9.     cluster: demo2
    10.     clusterNamespace: test2
    11.     # logLevel: info
    12.     # statusAddr: ${status_addr}
    13.     # concurrency: 4
    14.     # rateLimit: 0
    15.     # timeAgo: ${time}
    16.     # checksum: true
    17.     # sendCredToTikv: true
    18.   # # Only needed for TiDB Operator < v1.1.10 or TiDB < v4.0.8
    19.   # to:
    20.   #   host: ${tidb_host}
    21.   #   port: ${tidb_port}
    22.   #   user: ${tidb_user}
    23.   #   secretName: restore-demo2-tidb-secret
    24.   s3:
    25.     provider: aws
    26.     secretName: s3-secret
    27.     region: us-west-1
    28.     bucket: my-bucket
    29.     prefix: my-folder

  • Method 2: If you grant permissions by associating IAM with Pod, create the Restore CR to restore cluster data as described below:

    1. kubectl apply -f restore-aws-s3.yaml

    The content of restore-aws-s3.yaml is as follows:

    1. ---
    2. apiVersion: pingcap.com/v1alpha1
    3. kind: Restore
    4. metadata:
    5.  name: demo2-restore-s3
    6.  namespace: test2
    7.  annotations:
    8.    iam.amazonaws.com/role: arn:aws:iam::123456789012:role/user
    9. spec:
    10.  br:
    11.    cluster: demo2
    12.    sendCredToTikv: false
    13.    clusterNamespace: test2
    14.    # logLevel: info
    15.    # statusAddr: ${status_addr}
    16.    # concurrency: 4
    17.    # rateLimit: 0
    18.    # timeAgo: ${time}
    19.    # checksum: true
    20.  # Only needed for TiDB Operator < v1.1.10 or TiDB < v4.0.8
    21.  to:
    22.    host: ${tidb_host}
    23.    port: ${tidb_port}
    24.    user: ${tidb_user}
    25.    secretName: restore-demo2-tidb-secret
    26.  s3:
    27.    provider: aws
    28.    region: us-west-1
    29.    bucket: my-bucket
    30.    prefix: my-folder

  • Method 3: If you grant permissions by associating IAM with ServiceAccount, create the Restore CR to restore cluster data as described below:

    1. kubectl apply -f restore-aws-s3.yaml

    The content of restore-aws-s3.yaml is as follows:

    1. ---
    2. apiVersion: pingcap.com/v1alpha1
    3. kind: Restore
    4. metadata:
    5.   name: demo2-restore-s3
    6.   namespace: test2
    7. spec:
    8.   serviceAccount: tidb-backup-manager
    9.   br:
    10.     cluster: demo2
    11.     sendCredToTikv: false
    12.     clusterNamespace: test2
    13.     # logLevel: info
    14.     # statusAddr: ${status_addr}
    15.     # concurrency: 4
    16.     # rateLimit: 0
    17.     # timeAgo: ${time}
    18.     # checksum: true
    19.   # Only needed for TiDB Operator < v1.1.10 or TiDB < v4.0.8
    20.   to:
    21.     host: ${tidb_host}
    22.     port: ${tidb_port}
    23.     user: ${tidb_user}
    24.     secretName: restore-demo2-tidb-secret
    25.   s3:
    26.     provider: aws
    27.     region: us-west-1
    28.     bucket: my-bucket
    29.     prefix: my-folder

When configuring restore-aws-s3.yaml, note the following:

  • For more information about S3-compatible storage configuration, refer to S3 storage fields.
  • Some parameters in .spec.br are optional, such as logLevel, statusAddr, concurrency, rateLimit, checksum, timeAgo, and sendCredToTikv. For more information about BR configuration, refer to BR fields.
  • For v4.0.8 or a later version, BR can automatically adjust tikv_gc_life_time. You do not need to configure spec.to fields in the Restore CR.
  • For more information about the Restore CR fields, refer to Restore CR fields.

After creating the Restore CR, execute the following command to check the restore status:

  1. kubectl get rt -n test2 -o wide

Troubleshooting

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