# Configuring delayed replication with MariaDB
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You can use delayed replication as a strategy for disaster recovery. With delayed replication, you specify the minimum amount of time, in seconds, to delay replication from the source to the read replica. In the event of a disaster, such as a table deleted unintentionally, you complete the following steps to recover from the disaster quickly:
+ Stop replication to the read replica before the change that caused the disaster is sent to it.

  To stop replication, use the [mysql.rds\$1stop\$1replication](mysql-stored-proc-replicating.md#mysql_rds_stop_replication) stored procedure.
+ Promote the read replica to be the new source DB instance by using the instructions in [Promoting a read replica to be a standalone DB instance](USER_ReadRepl.Promote.md).

**Note**  
Delayed replication is supported for MariaDB 10.6 and higher.
Use stored procedures to configure delayed replication. You can't configure delayed replication with the AWS Management Console, the AWS CLI, or the Amazon RDS API.
You can use replication based on global transaction identifiers (GTIDs) in a delayed replication configuration.

**Topics**
+ [Configuring delayed replication during read replica creation](#USER_MariaDB.Replication.ReadReplicas.DelayReplication.ReplicaCreation)
+ [Modifying delayed replication for an existing read replica](#USER_MariaDB.Replication.ReadReplicas.DelayReplication.ExistingReplica)
+ [Promoting a read replica](#USER_MariaDB.Replication.ReadReplicas.DelayReplication.Promote)

## Configuring delayed replication during read replica creation
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To configure delayed replication for any future read replica created from a DB instance, run the [mysql.rds\$1set\$1configuration](mysql-stored-proc-configuring.md#mysql_rds_set_configuration) stored procedure with the `target delay` parameter.

**To configure delayed replication during read replica creation**

1. Using a MariaDB client, connect to the MariaDB DB instance to be the source for read replicas as the master user.

1. Run the [mysql.rds\$1set\$1configuration](mysql-stored-proc-configuring.md#mysql_rds_set_configuration) stored procedure with the `target delay` parameter.

   For example, run the following stored procedure to specify that replication is delayed by at least one hour (3,600 seconds) for any read replica created from the current DB instance.

   ```
   call mysql.rds_set_configuration('target delay', 3600);
   ```
**Note**  
After running this stored procedure, any read replica you create using the AWS CLI or Amazon RDS API is configured with replication delayed by the specified number of seconds.

## Modifying delayed replication for an existing read replica
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To modify delayed replication for an existing read replica, run the [mysql.rds\$1set\$1source\$1delay](mysql-stored-proc-replicating.md#mysql_rds_set_source_delay) stored procedure.

**To modify delayed replication for an existing read replica**

1. Using a MariaDB client, connect to the read replica as the master user.

1. Use the [mysql.rds\$1stop\$1replication](mysql-stored-proc-replicating.md#mysql_rds_stop_replication) stored procedure to stop replication.

1. Run the [mysql.rds\$1set\$1source\$1delay](mysql-stored-proc-replicating.md#mysql_rds_set_source_delay) stored procedure.

   For example, run the following stored procedure to specify that replication to the read replica is delayed by at least one hour (3600 seconds).

   ```
   call mysql.rds_set_source_delay(3600);
   ```

1. Use the [mysql.rds\$1start\$1replication](mysql-stored-proc-replicating.md#mysql_rds_start_replication) stored procedure to start replication.

## Promoting a read replica
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After replication is stopped, in a disaster recovery scenario, you can promote a read replica to be the new source DB instance. For information about promoting a read replica, see [Promoting a read replica to be a standalone DB instance](USER_ReadRepl.Promote.md).