Setting and showing binary log configuration
The following stored procedures set and show configuration parameters, such as for binary log file retention.
mysql.rds_set_configuration
Specifies the number of hours to retain binary logs or the number of seconds to delay replication.
Syntax
CALL mysql.rds_set_configuration(
name
,value
);
Parameters
-
name
-
The name of the configuration parameter to set.
-
value
-
The value of the configuration parameter.
Usage notes
The mysql.rds_set_configuration
procedure supports the following configuration parameters:
The configuration parameters are stored permanently and survive any DB instance reboot or failover.
binlog retention hours
The binlog retention hours
parameter is used to specify the number of hours to retain
binary log files. Amazon RDS normally purges a binary log as soon as possible, but the binary log might still be required for
replication with a MySQL database external to RDS.
The default value of binlog retention hours
is NULL
. For RDS for MySQL,
NULL
means binary logs aren't retained (0 hours).
To specify the number of hours to retain binary logs on a DB instance, use the mysql.rds_set_configuration
stored procedure and specify a
period with enough time for replication to occur, as shown in the following example.
call mysql.rds_set_configuration('binlog retention hours', 24);
Note
You can't use the value 0
for binlog retention hours
.
For MySQL DB instances, the maximum binlog retention hours
value is 168 (7 days).
After you set the retention period, monitor storage usage for the DB instance to make sure that the retained binary logs don't take up too much storage.
For Multi-AZ DB cluster deployments, you can only configure binary log retention from the writer DB instance, and the setting is propagated to all reader DB instances asynchronously. If binary logs on the DB cluster exceed half of the total local storage space, Amazon RDS automatically moves stale logs to the EBS volume. However, the newest logs remain in local storage, so they're subject to be lost if there's a failure that requires a host replacement, or if you scale the database up or down.
source delay
Use the source delay
parameter in a read replica to specify the number of seconds to delay replication
from the read replica to its source DB instance. Amazon RDS normally replicates changes as soon as possible, but you might
want some environments to delay replication. For example, when replication is delayed, you can roll forward a delayed
read replica to the time just before a disaster. If a table is dropped accidentally, you can use delayed replication to
quickly recover it. The default value of target delay
is 0
(don't delay
replication).
When you use this parameter, it runs mysql.rds_set_source_delay and applies CHANGE primary TO MASTER_DELAY = input value. If
successful, the procedure saves the source delay
parameter to the mysql.rds_configuration
table.
To specify the number of seconds for Amazon RDS to delay replication to a source DB instance, use the
mysql.rds_set_configuration
stored procedure and specify the number of seconds to delay replication. In
the following example, the replication is delayed by at least one hour (3,600 seconds).
call mysql.rds_set_configuration('source delay', 3600);
The procedure then runs mysql.rds_set_source_delay(3600)
.
The limit for the source delay
parameter is one day (86400 seconds).
Note
The source delay
parameter isn't supported for RDS for MySQL version 8.0 or MariaDB versions below
10.2.
target delay
Use the target delay
parameter to specify the number of seconds to delay replication between a DB
instance and any future RDS-managed read replicas created from this instance. This parameter is ignored for
non-RDS-managed read replicas. Amazon RDS normally replicates changes as soon as possible, but you might want some
environments to delay replication. For example, when replication is delayed, you can roll forward a delayed read replica
to the time just before a disaster. If a table is dropped accidentally, you can use delayed replication to recover it
quickly. The default value of target delay
is 0
(don't delay replication).
For disaster recovery, you can use this configuration parameter with the mysql.rds_start_replication_until stored procedure or
the mysql.rds_start_replication_until_gtid
stored procedure. To roll forward changes to a delayed read replica to the time just before a disaster, you can run the
mysql.rds_set_configuration
procedure with this parameter set. After the
mysql.rds_start_replication_until
or mysql.rds_start_replication_until_gtid
procedure
stops replication, you can promote the read replica to be the new primary DB instance by using the instructions in Promoting a read replica to be a standalone DB instance.
To use the mysql.rds_rds_start_replication_until_gtid
procedure, GTID-based replication must be enabled.
To skip a specific GTID-based transaction that is known to cause disaster, you can use the mysql.rds_skip_transaction_with_gtid stored
procedure. For more information about working with GTID-based replication, see Using GTID-based replication.
To specify the number of seconds for Amazon RDS to delay replication to a read replica, use the
mysql.rds_set_configuration
stored procedure and specify the number of seconds to delay replication.
The following example specifies that replication is delayed by at least one hour (3,600 seconds).
call mysql.rds_set_configuration('target delay', 3600);
The limit for the target delay
parameter is one day (86400 seconds).
Note
The target delay
parameter isn't supported for
RDS for MySQL version 8.0 or MariaDB versions earlier than 10.2.
mysql.rds_show_configuration
The number of hours that binary logs are retained.
Syntax
CALL mysql.rds_show_configuration;
Usage notes
To verify the number of hours that Amazon RDS retains binary logs, use the
mysql.rds_show_configuration
stored procedure.
Examples
The following example displays the retention period:
call mysql.rds_show_configuration; name value description binlog retention hours 24 binlog retention hours specifies the duration in hours before binary logs are automatically deleted.