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Settings for DB instances - Amazon Relational Database Service

Settings for DB instances

In the following table, you can find details about which settings you can and can't modify. You can also find when changes can be applied and whether the changes cause downtime for your DB instance. By using Amazon RDS features such as Multi-AZ, you can minimize downtime if you later modify the DB instance. For more information, see Configuring and managing a Multi-AZ deployment for Amazon RDS.

You can modify a DB instance using the console, the modify-db-instance CLI command, or the ModifyDBInstance RDS API operation.

Console setting and description CLI option and RDS API parameter When the change occurs Downtime notes Supported DB engines

Allocated storage

The storage, in gibibytes, that you want to allocate for your DB instance. You can only increase the allocated storage. You can't reduce the allocated storage.

You can't modify the storage of some older DB instances, or DB instances restored from older DB snapshots. The Allocated storage setting is disabled in the console if your DB instance isn't eligible. You can check whether you can allocate more storage by using the CLI command describe-valid-db-instance-modifications. This command returns the valid storage options for your DB instance.

You can't modify allocated storage if the DB instance status is storage-optimization. You can perform a maximum of four storage modifications on a DB instance within any 24-hour period. To monitor optimization progress per volume, use the StorageOperationStatus and StorageOperationPercentProgress fields in the DescribeDBInstances response.

The maximum storage allowed depends on your DB engine and the storage type. For more information, see Amazon RDS DB instance storage.

CLI option:

--allocated-storage

RDS API parameter:

AllocatedStorage

If you choose to apply the change immediately, it occurs immediately.

If you don't choose to apply the change immediately, it occurs during the next maintenance window.

Downtime doesn't occur during this change. Performance might be degraded during the change.

All DB engines

Architecture configuration

A configuration that allows multiple tenant databases to reside in your DB instance. Currently, only RDS for Oracle container databases (CDBs) support this setting.

If your CDB is in the single-tenant configuration, you can modify it to use the Multi-tenant configuration. In this configuration, you can use RDS APIs to create 1–30 tenant databases, depending on the database edition and any required option licenses. Application PDBs and proxy PDBs aren't supported. The multi-tenant configuration is permanent, which means that you can't later convert your CDB back to the single-tenant configuration.

Note

The Amazon RDS configuration is called "multi-tenant" rather than "multitenant" because it is a capability of Amazon RDS, not just the Oracle DB engine. Similarly, the RDS term "tenant" refers to any tenant in an RDS configuration, not just Oracle PDBs. In the RDS documentation, the unhyphenated term "Oracle multitenant" refers exclusively to the Oracle database CDB architecture, which is compatible with both on-premises and RDS deployments.

For more information, see Overview of RDS for Oracle CDBs.

CLI option:

--multi-tenant (multi-tenant configuration of the CDB architecture)

--no-multi-tenant (single-tenant configuration of the CDB architecture)

API parameter:

MultiTenant

The change occurs immediately.

Downtime doesn't occur during this change.

Oracle

Architecture settings

The architecture of the Oracle database: CDB or non-CDB. If you choose Oracle multitenant architecture, RDS for Oracle converts your non-CDB into a CDB that uses the single-tenant configuration.

This setting is supported only if your database is a non-CDB running Oracle Database 19c with the April 2021 or higher RU. After conversion, your CDB contains one initial pluggable database (PDB). The architecture change is permanent, which means that you can't convert your CDB back to a non-CDB.

Note

To convert a CDB in the single-tenant configuration to the multi-tenant configuration, modify your CDB instance again and choose Multi-tenant configuration for your Architecture configuration.

For more information, see Single-tenant configuration of the CDB architecture.

CLI option:

--engine oracle-ee-cdb (Oracle multitenant)

--engine oracle-se2-cdb (Oracle multitenant)

API parameter:

Engine

If you choose to apply the change immediately, it occurs immediately.

If you don't choose to apply the change immediately, it occurs during the next maintenance window.

Downtime occurs during this change.

Oracle

Auto minor version upgrade

Choose Enable auto minor version upgrade to enable your DB instance to receive preferred minor DB engine version upgrades automatically when they become available. This is the default behavior. Amazon RDS performs automatic minor version upgrades in the maintenance window. If you don't choose Enable auto minor version upgrade, your DB instance isn't upgraded automatically when new minor versions become available.

For more information, see Automatically upgrading the minor engine version.

CLI option:

--auto-minor-version-upgrade | --no-auto-minor-version-upgrade

RDS API parameter:

AutoMinorVersionUpgrade

The change occurs immediately. This setting ignores the apply immediately setting.

Downtime doesn't occur during this change.

All DB engines

Backup replication

Choose Enable replication to another AWS Region to create backups in an additional Region for disaster recovery.

Then choose the Destination Region for the additional backups.

Not available when modifying a DB instance. For information on enabling cross-Region backups using the AWS CLI or RDS API, see Enabling cross-Region automated backups for Amazon RDS.

The change is applied asynchronously, as soon as possible.

Downtime doesn't occur during this change.

 All DB engines

Backup retention period

The number of days that automatic backups are retained. To disable automatic backups, set the backup retention period to 0.

For more information, see Introduction to backups.

Note

If you use AWS Backup to manage your backups, this option doesn't apply. For information about AWS Backup, see the AWS Backup Developer Guide.

CLI option:

--backup-retention-period

RDS API parameter:

BackupRetentionPeriod

If you choose to apply the change immediately, it occurs immediately.

If you don't choose to apply the change immediately, and you change the setting from a nonzero value to another nonzero value, the change is applied asynchronously, as soon as possible. Otherwise, the change occurs during the next maintenance window.

Downtime occurs if you change from 0 to a nonzero value, or from a nonzero value to 0.

This applies to both Single-AZ and Multi-AZ DB instances.

All DB engines

Backup window

The time range during which automated backups of your databases occur. The backup window is a start time in Universal Coordinated Time (UTC), and a duration in hours.

For more information, see Introduction to backups.

Note

If you use AWS Backup to manage your backups, this option doesn't appear. For information about AWS Backup, see the AWS Backup Developer Guide.

CLI option:

--preferred-backup-window

RDS API parameter:

PreferredBackupWindow

The change is applied asynchronously, as soon as possible.

Downtime doesn't occur during this change.

All DB engines

Certificate authority

The certificate authority (CA) for the server certificate used by the DB instance.

For more information, see Using SSL/TLS to encrypt a connection to a DB instance or cluster .

CLI option:

--ca-certificate-identifier

RDS API parameter:

CACertificateIdentifier

If you choose to apply the change immediately, it occurs immediately.

If you don't choose to apply the change immediately, it occurs during the next maintenance window.

Downtime only occurs if the DB engine doesn't support rotation without restart. You can use the describe-db-engine-versions AWS CLI command to determine whether the DB engine supports rotation without restart.

All DB engines

Copy tags to snapshots

If you have any DB instance tags, enable this option to copy them when you create a DB snapshot.

For more information, see Tagging Amazon RDS resources.

CLI option:

--copy-tags-to-snapshot or --no-copy-tags-to-snapshot

RDS API parameter:

CopyTagsToSnapshot

The change occurs immediately. This setting ignores the apply immediately setting.

Downtime doesn't occur during this change.

All DB engines

Database port

The port that you want to use to access the DB instance.

The port value must not match any of the port values specified for options in the option group that is associated with the DB instance.

For more information, see Connecting to an Amazon RDS DB instance.

CLI option:

--db-port-number

RDS API parameter:

DBPortNumber

The change occurs immediately. This setting ignores the apply immediately setting.

The DB instance is rebooted immediately.

All DB engines

DB engine version

The version of the DB engine that you want to use. Before you upgrade your production DB instance, we recommend that you test the upgrade process on a test DB instance. Doing this helps verify its duration and validate your applications.

For more information, see Upgrading a DB instance engine version.

CLI option:

--engine-version

RDS API parameter:

EngineVersion

If you choose to apply the change immediately, it occurs immediately.

If you don't choose to apply the change immediately, it occurs during the next maintenance window.

Downtime occurs during this change.

All DB engines

DB instance class

The DB instance class that you want to use.

For more information, see DB instance classes.

CLI option:

--db-instance-class

RDS API parameter:

DBInstanceClass

If you choose to apply the change immediately, it occurs immediately.

If you don't choose to apply the change immediately, it occurs during the next maintenance window.

Downtime occurs during this change.

All DB engines

DB instance identifier

The new DB instance identifier. This value is stored as a lowercase string.

For more information about the effects of renaming a DB instance, see Renaming a DB instance.

CLI option:

--new-db-instance-identifier

RDS API parameter:

NewDBInstanceIdentifier

If you choose to apply the change immediately, it occurs immediately.

If you don't choose to apply the change immediately, it occurs during the next maintenance window.

Downtime occurs during this change unless your DB engine version supports dynamic SSL upload. To determine whether your version requires a restart, run the following AWS CLI command:

aws rds describe-db-engine-versions \
--default-only \
--engine your-db-engine \
--query 'DBEngineVersions[*].SupportsCertificateRotationWithoutRestart'

All DB engines

DB parameter group

The DB parameter group that you want associated with the DB instance.

For more information, see Parameter groups for Amazon RDS.

CLI option:

--db-parameter-group-name

RDS API parameter:

DBParameterGroupName

The association of the new DB parameter group with the DB instance occurs immediately.

Downtime doesn't occur when you associate a new DB parameter group with your DB instance.

The association of a DB parameter group is different from the application of parameter changes within a parameter group. RDS applies modified static and dynamic parameter settings in the newly associated group only after you manually reboot the DB instance. However, if you modify dynamic parameters in the DB parameter group after you associate it with the DB instance, these parameter settings are applied immediately without requiring a reboot.

For more information, see Parameter groups for Amazon RDS and Rebooting a DB instance.

All DB engines

Dedicated Log Volume

Use a dedicated log volume (DLV) to store database transaction logs on a storage volume that's separate from the volume containing the database tables.