Configuring binary log file position replication with an external source instance
You can set up replication between an RDS for MySQL or MariaDB DB instance and a MySQL or MariaDB instance that is external to Amazon RDS using binary log file replication.
Topics
Before you begin
You can configure replication using the binary log file position of replicated transactions.
The permissions required to start replication on an Amazon RDS DB instance are restricted and not available to your Amazon RDS master user. Because of this, make sure that you use the Amazon RDS mysql.rds_set_external_master (RDS for MariaDB and RDS for MySQL major versions 8.0 and lower) or mysql.rds_set_external_source (RDS for MySQL major versions 8.4 and higher), and mysql.rds_start_replication commands to set up replication between your live database and your Amazon RDS database.
To set the binary logging format for a MySQL or MariaDB database, update the
binlog_format
parameter. If your DB instance uses the default DB
instance parameter group, create a new DB parameter group to modify the
binlog_format
parameter. In MariaDB and MySQL 8.0 and lower versions,
binlog_format
defaults to MIXED
. However, you can also set
binlog_format
to ROW
or STATEMENT
if you need
a specific binary log (binlog) format. Reboot your DB instance for the change to take
effect. In MySQL 8.4 and higher versions, binlog_format
defaults to
ROW
.
For information about setting the binlog_format
parameter, see
Configuring RDS for MySQL binary logging.
For information about the implications of different MySQL replication types, see
Advantages
and disadvantages of statement-based and row-based replication
Configuring binary log file position replication with an external source instance
Follow these guidelines when you set up an external source instance and a replica on Amazon RDS:
Monitor failover events for the Amazon RDS DB instance that is your replica. If a failover occurs, then the DB instance that is your replica might be recreated on a new host with a different network address. For information on how to monitor failover events, see Working with Amazon RDS event notification.
Maintain the binlogs on your source instance until you have verified that they have been applied to the replica. This maintenance makes sure that you can restore your source instance in the event of a failure.
Turn on automated backups on your Amazon RDS DB instance. Turning on automated backups makes sure that you can restore your replica to a particular point in time if you need to re-synchronize your source instance and replica. For information on backups and point-in-time restore, see Backing up, restoring, and exporting data.
To configure binary log file replication with an external source instance
-
Make the source MySQL or MariaDB instance read-only.
mysql> FLUSH TABLES WITH READ LOCK; mysql> SET GLOBAL read_only = ON;
-
Run the
SHOW MASTER STATUS
command on the source MySQL or MariaDB instance to determine the binlog location.You receive output similar to the following example.
File Position ------------------------------------ mysql-bin-changelog.000031 107 ------------------------------------
-
Copy the database from the external instance to the Amazon RDS DB instance using
mysqldump
. For very large databases, you might want to use the procedure in Importing data to an Amazon RDS MariaDB or MySQL database with reduced downtime.For Linux, macOS, or Unix:
mysqldump --databases
database_name
\ --single-transaction \ --compress \ --order-by-primary \ -ulocal_user
\ -plocal_password
| mysql \ --host=hostname \ --port=3306 \ -uRDS_user_name
\ -pRDS_password
For Windows:
mysqldump --databases
database_name
^ --single-transaction ^ --compress ^ --order-by-primary ^ -ulocal_user
^ -plocal_password
| mysql ^ --host=hostname ^ --port=3306 ^ -uRDS_user_name
^ -pRDS_password
Note
Make sure that there isn't a space between the
-p
option and the entered password.To specify the host name, user name, port, and password to connect to your Amazon RDS DB instance, use the
--host
,--user (-u)
,--port
and-p
options in themysql
command. The host name is the Domain Name Service (DNS) name from the Amazon RDS DB instance endpoint, for examplemyinstance.123456789012.us-east-1.rds.amazonaws.com
. You can find the endpoint value in the instance details in the Amazon Web Services Management Console. -
Make the source MySQL or MariaDB instance writeable again.
mysql> SET GLOBAL read_only = OFF; mysql> UNLOCK TABLES;
For more information on making backups for use with replication, see the MySQL documentation
. -
In the Amazon Web Services Management Console, add the IP address of the server that hosts the external database to the virtual private cloud (VPC) security group for the Amazon RDS DB instance. For more information on modifying a VPC security group, see Security groups for your VPC in the Amazon Virtual Private Cloud User Guide.
The IP address can change when the following conditions are met:
-
You are using a public IP address for communication between the external source instance and the DB instance.
-
The external source instance was stopped and restarted.
If these conditions are met, verify the IP address before adding it.
You might also need to configure your local network to permit connections from the IP address of your Amazon RDS DB instance. You do this so that your local network can communicate with your external MySQL or MariaDB instance. To find the IP address of the Amazon RDS DB instance, use the
host
command.host
db_instance_endpoint
The host name is the DNS name from the Amazon RDS DB instance endpoint.
-
-
Using the client of your choice, connect to the external instance and create a user to use for replication. Use this account solely for replication and restrict it to your domain to improve security. The following is an example.
CREATE USER '
repl_user'@'mydomain.com
' IDENTIFIED BY 'password
';Note
Specify a password other than the prompt shown here as a security best practice.
-
For the external instance, grant
REPLICATION CLIENT
andREPLICATION SLAVE
privileges to your replication user. For example, to grant theREPLICATION CLIENT
andREPLICATION SLAVE
privileges on all databases for the 'repl_user
' user for your domain, issue the following command.GRANT REPLICATION CLIENT, REPLICATION SLAVE ON *.* TO '
repl_user'@'mydomain.com
'; -
Make the Amazon RDS DB instance the replica. To do so, first connect to the Amazon RDS DB instance as the master user. Then identify the external MySQL or MariaDB database as the source instance by using the mysql.rds_set_external_source (RDS for MySQL major versions 8.4 and higher) or mysql.rds_set_external_master (RDS for MariaDB and RDS for MySQL major versions 8.0 and lower) command. Use the master log file name and master log position that you determined in step 2. The following commands are examples.
MySQL 8.4
CALL mysql.rds_set_external_source ('
mysourceserver.mydomain.com
', 3306, 'repl_user
', 'password
', 'mysql-bin-changelog.000031
',107
,1
);MariaDB and MySQL 8.0 and 5.7
CALL mysql.rds_set_external_master ('
mymasterserver.mydomain.com
', 3306, 'repl_user
', 'password
', 'mysql-bin-changelog.000031
',107
,1
);Note
On RDS for MySQL, you can choose to use delayed replication by running the mysql.rds_set_external_source_with_delay (RDS for MySQL major versions 8.4 and higher) or mysql.rds_set_external_master_with_delay (RDS for MariaDB and RDS for MySQL major versions 8.0 and lower) stored procedure instead. On RDS for MySQL, one reason to use delayed replication is to turn on disaster recovery with the mysql.rds_start_replication_until stored procedure. Currently, RDS for MariaDB supports delayed replication but doesn't support the
mysql.rds_start_replication_until
procedure. -
On the Amazon RDS DB instance, issue the mysql.rds_start_replication command to start replication.
CALL mysql.rds_start_replication;