How to create and manage read replicas in Azure Database for MySQL using the Azure portal

In this article, you will learn how to create and manage read replicas in the Azure Database for MySQL service using the Azure portal.

Important

You can create a read replica in the same region as your master server, or in any other Azure region of your choice. Cross-region replication is currently in public preview.

Prerequisites

Important

The read replica feature is only available for Azure Database for MySQL servers in the General Purpose or Memory Optimized pricing tiers. Ensure the master server is in one of these pricing tiers.

Create a read replica

A read replica server can be created using the following steps:

  1. Sign into the Azure portal.

  2. Select the existing Azure Database for MySQL server that you want to use as a master. This action opens the Overview page.

  3. Select Replication from the menu, under SETTINGS.

  4. Select Add Replica.

    Azure Database for MySQL - Replication

  5. Enter a name for the replica server.

    Azure Database for MySQL - Replica name

  6. Select the location for the replica server. You can create a replica in any Azure region. The default location is the same as the master server

    Azure Database for MySQL - Replica location

  7. Select OK to confirm creation of the replica.

Note

Read replicas are created with the same server configuration as the master. The replica server configuration can be changed after it has been created. It is recommended that the replica server's configuration should be kept at equal or greater values than the master to ensure the replica is able to keep up with the master.

Once the replica server has been created, it can be viewed from the Replication blade.

Azure Database for MySQL - List replicas

Stop replication to a replica server

Important

Stopping replication to a server is irreversible. Once replication has stopped between a master and replica, it cannot be undone. The replica server then becomes a standalone server and now supports both read and writes. This server cannot be made into a replica again.

To stop replication between a master and a replica server from the Azure portal, use the following steps:

  1. In the Azure portal, select your master Azure Database for MySQL server.

  2. Select Replication from the menu, under SETTINGS.

  3. Select the replica server you wish to stop replication for.

    Azure Database for MySQL - Stop replication select server

  4. Select Stop replication.

    Azure Database for MySQL - Stop replication

  5. Confirm you want to stop replication by clicking OK.

    Azure Database for MySQL - Stop replication confirm

Delete a replica server

To delete a read replica server from the Azure portal, use the following steps:

  1. In the Azure portal, select your master Azure Database for MySQL server.

  2. Select Replication from the menu, under SETTINGS.

  3. Select the replica server you wish to delete.

    Azure Database for MySQL - Delete replica select server

  4. Select Delete replica

    Azure Database for MySQL - Delete replica

  5. Type the name of the replica and click Delete to confirm deletion of the replica.

    Azure Database for MySQL - Delete replica confirm

Delete a master server

Important

Deleting a master server stops replication to all replica servers and deletes the master server itself. Replica servers become standalone servers that now support both read and writes.

To delete a master server from the Azure portal, use the following steps:

  1. In the Azure portal, select your master Azure Database for MySQL server.

  2. From the Overview, select Delete.

    Azure Database for MySQL - Delete master

  3. Type the name of the master server and click Delete to confirm deletion of the master server.

    Azure Database for MySQL - Delete master

Monitor replication

  1. In the Azure portal, select the replica Azure Database for MySQL server you want to monitor.

  2. Under the Monitoring section of the sidebar, select Metrics:

  3. Select Replication lag in seconds from the dropdown list of available metrics.

    Select Replication lag

  4. Select the time range you wish to view. The image below selects a 30 minute time range.

    Select time range

  5. View the replication lag for the selected time range. The image below displays the last 30 minutes.

    Select time range

Next steps