Upgrading the Minor Version of a FlexusRDS for MySQL Instance

Scenarios

FlexusRDS for MySQL supports minor version upgrades to improve performance, add new functions, and fix bugs.

By default, a newly created DB instance uses the latest minor version. For details about minor kernel versions, see RDS for MySQL Kernel Version Description.

Precautions

• When any new minor version is released for addressing issues and vulnerabilities from the open source community, perform a minor version upgrade for your instance.
• The upgrade will cause the instance to reboot and interrupt services intermittently. To limit the impact of the upgrade, perform the upgrade during off-peak hours, or ensure that your applications support automatic reconnection.
• When a minor version is upgraded, the network is intermittently disconnected during the primary/standby switchover. In addition, semi-synchronous replication is performed between the primary and standby instances by default. During the upgrade, there can be two waits of up to 10s for a single SQL statement to update or write data. To avoid this problem, change the replication mode to asynchronous.
• If primary and standby DB instances are deployed in the same AZ, a minor version upgrade will trigger a failover. If primary and standby DB instances are deployed in different AZs, a minor version upgrade will trigger two failovers.
• A minor version upgrade cannot be rolled back after the upgrade is complete. If the upgrade fails, the DB instance will be automatically rolled back to the source version.
• A minor version can be upgraded in minutes.
• DDL operations on events, such as CREATE EVENT, DROP EVENT, and ALTER EVENT, are not allowed during a minor version upgrade.

  During a minor version upgrade, if you are prompted that there are DDL operations being executed on the primary instance, do as follows:

  • Change the status of the event whose STATUS is SLAVESIDE_DISABLED to ENABLED or DISABLED, and then perform the upgrade.
  • Delete the events whose STATUS is SLAVESIDE_DISABLED and then perform the upgrade.

Constraints

• If the replication delay between primary and standby DB instances is longer than 300 seconds, the minor version cannot be upgraded.
• For primary/standby DB instances, the standby DB instance is upgraded first and then the primary DB instance is upgraded afterwards.
• Minor versions cannot be upgraded for DB instances with abnormal nodes.
• TLSv1.1 is not supported for MySQL 8.0.28 or later versions. To modify the TLS version, change the value of the parameter loose_tls_version.

Procedure

1. In the instance list, click the target instance name.
2. On the Overview page, click Upgrade under the DB Engine Version field.
3. In the displayed dialog box, confirm the upgrade information and click OK.

   Upon submission: The system upgrades the minor version immediately after you have submitted your upgrade request.

   During the upgrade, the instance status is Upgrading minor version. After the upgrade is complete, the instance status changes to Available.