Restoring a cluster from a snapshot - Amazon Redshift
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Restoring a cluster from a snapshot

A snapshot contains data from any databases that are running on your cluster. It also contains information about your cluster, including the number of nodes, node type, and admin user name. If you restore your cluster from a snapshot, Amazon Redshift uses the cluster information to create a new cluster. Then it restores all the databases from the snapshot data.

For the new cluster created from the original snapshot, you can choose the configuration, such as node type and number of nodes. The cluster is restored in the same Amazon Region and a random, system-chosen Availability Zone, unless you specify another Availability Zone in your request. When you restore a cluster from a snapshot, you can optionally choose a compatible maintenance track for the new cluster.

Note

When you restore a snapshot to a cluster with a different configuration, the snapshot must have been taken on a cluster with cluster version 1.0.10013, or later.

When a restore is in progress, events are typically emitted in the following order:

  1. RESTORE_STARTED – REDSHIFT-EVENT-2008 sent when the restore process begins.

  2. RESTORE_SUCCEEDED – REDSHIFT-EVENT-3003 sent when the new cluster has been created.

    The cluster is available for queries.

  3. DATA_TRANSFER_COMPLETED – REDSHIFT-EVENT-3537 sent when data transfer complete.

Note

RA3 clusters only emit RESTORE_STARTED and RESTORE_SUCCEEDED events. There is no explicit data transfer to be done after a RESTORE succeeds because RA3 node types store data in Amazon Redshift managed storage. With RA3 nodes, data is continuously transferred between RA3 nodes and Amazon Redshift managed storage as part of normal query processing. RA3 nodes cache hot data locally and keep less frequently queried blocks in Amazon Redshift managed storage automatically.

You can monitor the progress of a restore by either calling the DescribeClusters API operation, or viewing the cluster details in the Amazon Web Services Management Console. For an in-progress restore, these display information such as the size of the snapshot data, the transfer rate, the elapsed time, and the estimated time remaining. For a description of these metrics, see RestoreStatus.

You can't use a snapshot to revert an active cluster to a previous state.

Note

When you restore a snapshot into a new cluster, the default security group and parameter group are used unless you specify different values.

You might want to restore a snapshot to a cluster with a different configuration for these reasons:

  • When a cluster is made up of smaller node types and you want to consolidate it into a larger node type with fewer nodes.

  • When you have monitored your workload and determined the need to move to a node type with more CPU and storage.

  • When you want to measure performance of test workloads with different node types.

Restore has the following constraints:

  • The new node configuration must have enough storage for existing data. Even when you add nodes, your new configuration might not have enough storage because of the way that data is redistributed.

  • The restore operation checks if the snapshot was created on a cluster version that is compatible with the cluster version of the new cluster. If the new cluster has a version level that is too early, then the restore operation fails and reports more information in an error message.

  • The possible configurations (number of nodes and node type) you can restore to is determined by the number of nodes in the original cluster and the target node type of the new cluster. To determine the possible configurations available, you can use the Amazon Redshift console or the describe-node-configuration-options Amazon CLI command with action-type restore-cluster. For more information about the restoring using the Amazon Redshift console, see Restoring a cluster from a snapshot.

The following steps take a cluster with many nodes and consolidate it into a bigger node type with a smaller number of nodes using the Amazon CLI. For this example, we start with a source cluster of 24 nodes. In this case, suppose that we already created a snapshot of this cluster and want to restore it into a bigger node type.

  1. Run the following command to get the details of our 24-node cluster. 

    aws redshift describe-clusters --region eu-west-1 --cluster-identifier mycluster-123456789012

  2. Run the following command to get the details of the snapshot. 

    aws redshift describe-cluster-snapshots --region eu-west-1 --snapshot-identifier mycluster-snapshot

  3. Run the following command to describe the options available for this snapshot. 

    aws redshift describe-node-configuration-options --snapshot-identifier mycluster-snapshot --region eu-west-1 --action-type restore-cluster

    This command returns an option list with recommended node types, number of nodes, and disk utilization for each option. For this example, the preceding command lists the following possible node configurations. We choose to restore into a three-node cluster.

    {
    "NodeConfigurationOptionList": [
        {
            "EstimatedDiskUtilizationPercent": 65.26134808858235,
            "NodeType": "dc2.large",
            "NumberOfNodes": 24
        },
        {
            "EstimatedDiskUtilizationPercent": 32.630674044291176,
            "NodeType": "dc2.large",
            "NumberOfNodes": 48
        },
        {
            "EstimatedDiskUtilizationPercent": 65.26134808858235,
            "NodeType": "dc2.8xlarge",
            "NumberOfNodes": 3
        },
        {
            "EstimatedDiskUtilizationPercent": 48.94601106643677,
            "NodeType": "dc2.8xlarge",
            "NumberOfNodes": 4
        },
        {
            "EstimatedDiskUtilizationPercent": 39.156808853149414,
            "NodeType": "dc2.8xlarge",
            "NumberOfNodes": 5
        },
        {
            "EstimatedDiskUtilizationPercent": 32.630674044291176,
            "NodeType": "dc2.8xlarge",
            "NumberOfNodes": 6
        }
    ]
}

  4. Run the following command to restore the snapshot into the cluster configuration that we chose. After this cluster is restored, we have the same content as the source cluster, but the data has been consolidated into three dc2.8xlarge nodes. 

    aws redshift restore-from-cluster-snapshot --region eu-west-1 --snapshot-identifier mycluster-snapshot --cluster-identifier mycluster-123456789012-x --node-type dc2.8xlarge --number-of-nodes 3

If you have reserved nodes, for example DC2 reserved nodes, you can upgrade to RA3 reserved nodes. You can do this when you restore from a snapshot or perform an elastic resize. You can use the console to guide you through this process. For more information about upgrading to RA3 nodes, see Upgrading to RA3 node types.

To restore a cluster from a snapshot on the console

  1. Sign in to the Amazon Web Services Management Console and open the Amazon Redshift console at https://console.amazonaws.cn/redshiftv2/.

  2. On the navigation menu, choose Clusters, Snapshots, then choose the snapshot to restore.

  3. Choose Restore from snapshot to view the Cluster configuration and Cluster details values of the new cluster to be created using the snapshot information.

  4. Update the properties of the new cluster, then choose Restore cluster from snapshot.

If Amazon Secrets Manager wasn't managing your cluster's admin password, you can have it manage your restored cluster by choosing Manage admin credentials in Amazon Secrets Manager in the Cluster configuration section and specifying a KMS key. Otherwise, the cluster is restored with the admin credentials it had at the time the snapshot was taken. You can update the cluster's admin credentials in the cluster detail page after restoring it.

If Amazon Secrets Manager managed your cluster's admin password at the time the snapshot was taken, you must continue using Amazon Secrets Manager to manage the admin password. You can opt out of using a secret after restoring the cluster by updating the cluster's admin credentials in the cluster detail page.

If you have reserved nodes, you can upgrade to RA3 reserved nodes. You can do this when you restore from a snapshot or perform an elastic resize. You can use the console to guide you through this process. For more information about upgrading to RA3 nodes, see Upgrading to RA3 node types.