Amazon DocumentDB Cluster Settings

When you create or modify a cluster, it is important to understand which parameters are immutable and which are modifiable after the cluster has been created. The following table lists all the settings, or parameters, that are specific to a cluster. As specified in the table, some are modifiable, others are not.

Note

These settings should not be confused with Amazon DocumentDB cluster parameter groups and their parameters. For more information about cluster parameter groups, see Managing Amazon DocumentDB Cluster Parameter Groups.

ParameterModifiableNotes
DBClusterIdentifierYes

Naming constraints:

  • Length is [1—63] letters, numbers, or hyphens.

  • First character must be a letter.

  • Cannot end with a hyphen or contain two consecutive hyphens.

  • Must be unique for all clusters across Amazon RDS, Amazon Neptune, and Amazon DocumentDB per AWS account, per Region.

EngineNoMust be docdb.
BackupRetentionPeriodYesMust be between [1-35] days.
DBClusterParameterGroupNameYes

Naming constraints:

  • Length is [1—255] alphanumeric characters.

  • First character must be a letter.

  • Cannot end with a hyphen or contain two consecutive hyphens.

DBSubnetGroupNameNoAfter a cluster has been created, you cannot modify the cluster’s subnet.
EngineVersionNoMust be 4.0.0.
KmsKeyIdNoIf you choose to encrypt your cluster, you cannot change the AWS KMS key that you used to encrypt your cluster.
MasterUsernameNo

After a cluster has been created, you cannot modify the MasterUsername.

Naming constraints:

  • Length is [1—63] alphanumeric characters.

  • First character must be a letter.

  • Cannot be a word reserved by the database engine.

MasterUserPasswordYes

Constraints:

  • Length is [8—100] printable ASCII characters.

  • Can use any printable ASCII characters except for the following:

    • / (forward slash)

    • “ (double quotation mark)

    • @ (at symbol)

PortYesThe port number applies to all instances in the cluster.
PreferredBackupWindowYes
PreferredMaintenanceWindowYes
StorageEncryptedNoIf you choose to encrypt your cluster, it cannot be unencrypted.
TagsYes
VpcSecurityGroupIdsNoAfter a cluster has been created, you cannot modify the VPC that the cluster resides in.