Maintenance time is a very important concept for TencentDB for MySQL. To ensure the stability of your TencentDB for MySQL instance, the backend system performs maintenance operations on the instance during the maintenance window from time to time. It is highly recommended that you set an acceptable maintenance time for your business instance, usually during off-peak hours, so as to minimize the potential impact on your business.
In addition, it is recommended that operations involving data migration be performed during the maintenance time too, such as instance specification adjustment, instance version upgrade, and instance kernel upgrade. Currently, the maintenance period concept is supported by master, read-only, and disaster recovery instances.
Take the database instance specification upgrade as an example. As this operation involves data migration, after the upgrade is completed, a momentary disconnection from the database may occur. When the upgrade is initiated, the switch time can be selected as during maintenance window, so that the instance specification switch will be enabled during the next maintenance window after the instance upgrade is completed. Please note that when you do so, the switch will not occur immediately after the database specification upgrade is completed; instead, the sync will continue till the instance goes into the next maintenance window when the switch will be performed. In this way, the overall time it takes to upgrade the instance may be extended.
- Before maintenance is carried out for TencentDB for MySQL, notifications will be sent to the contacts configured in your Tencent Cloud account through SMS and email.
- Instance switch is accompanied by a momentary disconnection from the database. Please make sure that your business has a reconnection mechanism.
If a task is configured to be switched during the maintenance window, but you need to switch it urgently under special circumstances, you can click Switch Now in the "Operation" column.
- Immediate switch is applicable to operations involving data migration such as instance specification adjustment, instance version upgrade, and instance kernel upgrade.
- For version upgrade, if an instance is associated with multiple instances, the switch will be performed in the order from disaster recovery instance to read-only instance to master instance.