Migrating a snapshot of an RDS for PostgreSQL DB instance to an Aurora PostgreSQL DB cluster - Amazon Aurora

Migrating a snapshot of an RDS for PostgreSQL DB instance to an Aurora PostgreSQL DB cluster

To create an Aurora PostgreSQL DB cluster, you can migrate a DB snapshot of an RDS for PostgreSQL DB instance. The new Aurora PostgreSQL DB cluster is populated with the data from the original RDS for PostgreSQL DB instance. For information about creating a DB snapshot, see Creating a DB snapshot.

In some cases, the DB snapshot might not be in the AWS Region where you want to locate your data. If so, use the Amazon RDS console to copy the DB snapshot to that AWS Region. For information about copying a DB snapshot, see Copying a DB snapshot.

You can migrate RDS for PostgreSQL snapshots that are compatible with the Aurora PostgreSQL versions available in the given AWS Region. For example, you can migrate a snapshot from an RDS for PostgreSQL 11.1 DB instance to Aurora PostgreSQL version 11.4, 11.7, 11.8, or 11.9 in the US West (N. California) Region. You can migrate RDS for PostgreSQL 10.11 snapshot to Aurora PostgreSQL 10.11, 10.12, 10.13, and 10.14. In other words, the RDS for PostgreSQL snapshot must use the same or a lower minor version as the Aurora PostgreSQL.

You can also choose for your new Aurora PostgreSQL DB cluster to be encrypted at rest by using an AWS KMS key. This option is available only for unencrypted DB snapshots.

To migrate an RDS for PostgreSQL DB snapshot to an Aurora PostgreSQL DB cluster, you can use the AWS Management Console, the AWS CLI, or the RDS API. When you use the AWS Management Console, the console takes the actions necessary to create both the DB cluster and the primary instance.

To migrate a PostgreSQL DB snapshot by using the RDS console

  1. Sign in to the AWS Management Console and open the Amazon RDS console at https://console.aws.amazon.com/rds/.

  2. Choose Snapshots.

  3. On the Snapshots page, choose the RDS for PostgreSQL snapshot that you want to migrate into an Aurora PostgreSQL DB cluster.

  4. Choose Actions then choose Migrate snapshot.

  5. Set the following values on the Migrate database page:

    • DB engine version: Choose a DB engine version you want to use for the new migrated instance.

    • DB instance identifier: Enter a name for the DB cluster that is unique for your account in the AWS Region that you chose. This identifier is used in the endpoint addresses for the instances in your DB cluster. You might choose to add some intelligence to the name, such as including the AWS Region and DB engine that you chose, for example aurora-cluster1.

      The DB instance identifier has the following constraints:

      • It must contain 1–63 alphanumeric characters or hyphens.

      • Its first character must be a letter.

      • It can't end with a hyphen or contain two consecutive hyphens.

      • It must be unique for all DB instances per AWS account, per AWS Region.

    • DB instance class: Choose a DB instance class that has the required storage and capacity for your database, for example db.r6g.large. Aurora cluster volumes automatically grow as the amount of data in your database increases. So you only need to choose a DB instance class that meets your current storage requirements. For more information, see Overview of Amazon Aurora storage.

    • Virtual private cloud (VPC): If you have an existing VPC, then you can use that VPC with your Aurora PostgreSQL DB cluster by choosing your VPC identifier, for example vpc-a464d1c1. For information about creating a VPC, see Tutorial: Create a VPC for use with a DB cluster (IPv4 only).

      Otherwise, you can choose to have Amazon RDS create a VPC for you by choosing Create new VPC.

    • DB subnet group: If you have an existing subnet group, then you can use that subnet group with your Aurora PostgreSQL DB cluster by choosing your subnet group identifier, for example gs-subnet-group1.

    • Public access: Choose No to specify that instances in your DB cluster can only be accessed by resources inside of your VPC. Choose Yes to specify that instances in your DB cluster can be accessed by resources on the public network.

      Note

      Your production DB cluster might not need to be in a public subnet, because only your application servers require access to your DB cluster. If your DB cluster doesn't need to be in a public subnet, set Public access to No.

    • VPC security group: Choose a VPC security group to allow access to your database.

    • Availability Zone: Choose the Availability Zone to host the primary instance for your Aurora PostgreSQL DB cluster. To have Amazon RDS choose an Availability Zone for you, choose No preference.

    • Database port: Enter the default port to be used when connecting to instances in the Aurora PostgreSQL DB cluster. The default is 5432.

      Note

      You might be behind a corporate firewall that doesn't allow access to default ports such as the PostgreSQL default port, 5432. In this case, provide a port value that your corporate firewall allows. Remember that port value later when you connect to the Aurora PostgreSQL DB cluster.

    • Enable Encryption: Choose Enable Encryption for your new Aurora PostgreSQL DB cluster to be encrypted at rest. Also choose a KMS key as the AWS KMS key value.

    • Auto minor version upgrade: Choose Enable auto minor version upgrade to enable your Aurora PostgreSQL DB cluster to receive minor PostgreSQL DB engine version upgrades automatically when they become available.

      The Auto minor version upgrade option only applies to upgrades to PostgreSQL minor engine versions for your Aurora PostgreSQL DB cluster. It doesn't apply to regular patches applied to maintain system stability.

  6. Choose Migrate to migrate your DB snapshot.

  7. Choose Databases to see the new DB cluster. Choose the new DB cluster to monitor the progress of the migration. When the migration completes, the Status for the cluster is Available. On the Connectivity & security tab, you can find the cluster endpoint to use for connecting to the primary writer instance of the DB cluster. For more information on connecting to an Aurora PostgreSQL DB cluster, see Connecting to an Amazon Aurora DB cluster.

Using the AWS CLI to migrate an RDS for PostgreSQL DB snapshot to an Aurora PostgreSQL involves two separate AWS CLI commands. First, you use the restore-db-cluster-from-snapshot AWS CLI command create a new Aurora PostgreSQL DB cluster. You then use the create-db-instance command to create the primary DB instance in the new cluster to complete the migration. The following procedure creates an Aurora PostgreSQL DB cluster with primary DB instance that has the same configuration as the DB instance used to create the snapshot.

To migrate an RDS for PostgreSQL DB snapshot to an Aurora PostgreSQL DB cluster

  1. Use the describe-db-snapshots command to obtain information about the DB snapshot you want to migrate. You can specify either the --db-instance-identifier parameter or the --db-snapshot-identifier in the command. If you don't specify one of these parameters, you get all snapshots. 

    aws rds describe-db-snapshots --db-instance-identifier <your-db-instance-name>

  2. The command returns all configuration details for any snapshots created from the DB instance specified. In the output, find the snapshot that you want to migrate and locate its Amazon Resource Name (ARN). To learn more about Amazon RDS ARNs, see Amazon Relational Database Service (Amazon RDS). An ARN looks similar to the output following.

    “DBSnapshotArn": "arn:aws:rds:aws-region:111122223333:snapshot:<snapshot_name>"

    Also in the output you can find configuration details for the RDS for PostgreSQL DB instance, such as the engine version, allocated storage, whether or not the DB instance is encrypted, and so on.

  3. Use the restore-db-cluster-from-snapshot command to start the migration. Specify the following parameters:

    • --db-cluster-identifier – The name that you want to give to the Aurora PostgreSQL DB cluster. This Aurora DB cluster is the target for your DB snapshot migration.

    • --snapshot-identifier – The Amazon Resource Name (ARN) of the DB snapshot to migrate.

    • --engine – Specify aurora-postgresql for the Aurora DB cluster engine.

    • --kms-key-id – This optional parameter lets you create an encrypted Aurora PostgreSQL DB cluster from an unencrypted DB snapshot. It also lets you choose a different encryption key for the DB cluster than the key used for the DB snapshot.

      Note

      You can't create an unencrypted Aurora PostgreSQL DB cluster from an encrypted DB snapshot.

    Without the --kms-key-id parameter specified as shown following, the restore-db-cluster-from-snapshot AWS CLI command creates an empty Aurora PostgreSQL DB cluster that's either encrypted using the same key as the DB snapshot or is unencrypted if the source DB snapshot isn't encrypted.

    For Linux, macOS, or Unix:

    aws rds restore-db-cluster-from-snapshot \
    --db-cluster-identifier cluster-name \
    --snapshot-identifier arn:aws:rds:aws-region:111122223333:snapshot:your-snapshot-name \
    --engine aurora-postgresql

    For Windows:

    aws rds restore-db-cluster-from-snapshot ^
    --db-cluster-identifier new_cluster ^
    --snapshot-identifier arn:aws:rds:aws-region:111122223333:snapshot:your-snapshot-name ^
    --engine aurora-postgresql

  4. The command returns details about the Aurora PostgreSQL DB cluster that's being created for the migration. You can check the status of the Aurora PostgreSQL DB cluster by using the describe-db-clusters AWS CLI command.

    aws rds describe-db-clusters --db-cluster-identifier cluster-name

  5. When the DB cluster becomes "available", you use create-db-instance command to populate the Aurora PostgreSQL DB cluster with the DB instance based on your Amazon RDS DB snapshot. Specify the following parameters:

    • --db-cluster-identifier – The name of the new Aurora PostgreSQL DB cluster that you created in the previous step.

    • --db-instance-identifier – The name you want to give to the DB instance. This instance becomes the primary node in your Aurora PostgreSQL DB cluster.

    • ----db-instance-class – Specify the DB instance class to use. Choose from among the DB instance classes supported by the Aurora PostgreSQL version to which you're migrating. For more information, see DB instance class types and Supported DB engines for DB instance classes.

    • --engine – Specify aurora-postgresql for the DB instance.

    You can also create the DB instance with a different configuration than the source DB snapshot, by passing in the appropriate options in the create-db-instance AWS CLI command. For more information, see the create-db-instance command.

    For Linux, macOS, or Unix:

    aws rds create-db-instance \
    --db-cluster-identifier cluster-name \
    --db-instance-identifier --db-instance-class db.instance.class \
    --engine aurora-postgresql

    For Windows:

    aws rds create-db-instance ^
    --db-cluster-identifier cluster-name ^
    --db-instance-identifier --db-instance-class db.instance.class ^
    --engine aurora-postgresql

When the migration process completes, the Aurora PostgreSQL cluster has a populated primary DB instance.