Adding Neptune Replicas to a DB Cluster - Amazon Neptune

Adding Neptune Replicas to a DB Cluster

In Neptune DB clusters, there is one primary DB instance and up to 15 Neptune replicas. The primary DB instance supports read and write operations, and performs all of the data modifications to the cluster volume. Neptune replicas connect to the same storage volume as the primary DB instance and support only read operations. Neptune replicas can offload read workloads from the primary DB instance.

We recommend that you distribute the primary instance and Neptune replicas in your DB cluster over multiple Availability Zones to improve the availability of your DB cluster.

For more information about Neptune replicas, see Creating a Neptune Replica Using the Console.

To add a Neptune replica to a DB cluster
  1. Sign in to the AWS Management Console, and open the Amazon Neptune console at

  2. In the navigation pane, choose Databases, and then choose a DB cluster.

  3. Choose Actions, and then choose Add reader.

    The Create read replica DB instance page appears.

  4. On the Create read replica DB instance page, specify options for your replica. The following table shows settings for a Neptune read replica.

    For This Option Do This

    DB instance class

    Choose a DB instance class with the processing and memory capacity that you want for your replica.

    Availability zone

    Determine whether you want to specify a particular availability zone (AZ). The list includes only those availability zones that are mapped by the DB subnet group of your DB cluster.


    If encryption at rest is not already enabled for instances in your DB cluster, select Enable encryption to enable it. For more information, see Encrypting Neptune Resources at Rest.

    Read replica source

    Select the identifier of the instance to create a read replica of.

    DB instance identifier

    Enter a name for the new instance that is unique in your account in the AWS region where your DB cluster is located. You might choose to include useful information in the name, such as the DB engine that you selected (for example gremlin-read-instance1).

    Database port

    The port for a Neptune replica is the same as the port for the DB cluster. The default is 8182.

    DB parameter group

    Choose a parameter group. Neptune has a default parameter group you can use, or you can create your own parameter group. For more information about parameter groups, see Amazon Neptune parameters.

    Audit log

    Select Audit log if you want to use audit logging through CloudWatch Logs. You must also set the neptune_enable_audit_log parameter in the DB cluster parameter group to enable (1) for audit logging to be enabled.

    Auto minor version upgrade

    Select Enable auto minor version upgrade if you want to enable your Neptune DB cluster to receive minor engine version upgrades automatically when they become available.

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

  5. Choose Create Neptune replica to create the Neptune replica.

To remove a Neptune replica from a DB cluster, follow the instructions in Deleting a DB Instance in Amazon Neptune to delete the Neptune replica DB instance.