Upgrading the Minor Version of a DB Instance

Scenarios

You can upgrade the minor version of your DB instance to improve performance, optimize functions, and fix bugs.

When a new minor version is released on Huawei Cloud, you will see Upgrade in the DB Engine Version column on the Instances page. You can click Upgrade to go to the minor version upgrade page.

For details about minor versions, see TaurusDB Kernel Version Release History.

Upgrade Methods

**Table 1** Upgrade methods
Upgrade Information	Upgrade Method	Description
Kernel version	There are three ways to upgrade the minor version based on different kernel versions: If the instance's kernel version is below 2.0.51.240305, it will be upgraded to 2.0.51.240305 first, followed by a minor version pre-upgrade and then a minor version upgrade. If the instance's kernel version is 2.0.51.240305, it will undergo a minor version pre-upgrade first. After that, you need to click Upgrade again to start a minor version upgrade. The following operations use this upgrade method as an example. If the instance's kernel version is above 2.0.51.240305, clicking Upgrade will directly trigger a minor version upgrade.	If the kernel version is 2.0.51.240305 or earlier, the upgrade involves changes to the underlying data dictionary and may take a long time. Binlog needs to be enabled for data dictionary upgrades. Ensure that the value of rds_global_sql_log_bin is ON and the value of binlog_expire_logs_seconds is at least 86400.
Upgrade time	There are two ways to upgrade the minor version based on different upgrade times. Upon submission: The system upgrades the minor version upon your manual submission of the upgrade request. In maintenance window: The system upgrades the minor version during the maintenance window you have specified. For details about how to change the maintenance window, see Changing the Maintenance Window of a DB Instance.	If the kernel version of your instance has potential risks or major defects, has expired, or has been brought offline, the system will notify you by SMS message or email and deliver an upgrade task during the maintenance window.

Constraints

**Table 2** Constraints
Phase	Constraint
Before the upgrade	To upgrade the kernel version to 2.0.54.240600 or later, ensure that rds_global_sql_log_bin is ON and binlog_expire_logs_seconds is greater than or equal to 86400. For details about how to set these parameters, see Modifying Parameters of a DB Instance. If the replication latency between the primary node and read replicas is longer than 300 seconds, the minor version cannot be upgraded. If you want to upgrade the minor version of your instance from 8.0.18 to 8.0.22 and there are more than 1,000 partitions, the upgrade may fail. Contact Huawei Cloud engineers to check the version compatibility before the upgrade.
During the upgrade	The upgrade will cause the instance to reboot and briefly interrupt workloads for about 30 to 90 seconds. To minimize the impact of the upgrade, perform the upgrade during off-peak hours, or ensure that your applications support automatic reconnection. If an instance contains a large number of table partitions (more than 1 million), it may take more than 2 hours to reboot the instance. If the primary node and read replicas of an instance are deployed in the same AZ, a minor version upgrade will trigger a failover. If they are in different AZs, a minor version upgrade will trigger two failovers. A failover means that the system fails over to a read replica in case the primary node is unavailable. When you upgrade the minor version of an instance, minor versions of read replicas (if any) will also be upgraded automatically. Minor versions of read replicas cannot be upgraded separately. Once you upgrade the minor version, the instance will be upgraded to the latest minor version. A minor version upgrade cannot be rolled back after the upgrade is complete. DDL operations on events, such as CREATE EVENT, DROP EVENT, and ALTER EVENT, are not allowed during a minor version upgrade. During the minor version pre-upgrade, the instance will not reboot, which means workloads will not be affected. The minor version upgrade will cause the instance to reboot, so workloads will be interrupted. The upgrade takes 15 to 20 minutes, and workloads are intermittently interrupted for 1 to 2 minutes. To minimize the impacts, perform the upgrade during off-peak hours. If the message "Upgrade failed. Reduce the service load of the instance and click Retry" is displayed on the console, the upgrade fails due to heavy service load. Reduce the service load or retry the upgrade during off-peak hours.
After the upgrade	If the upgrade fails, the instance will be rolled back to a previous version and its data will be restored to a new instance with the name original_instance_name_copy. The original instance will become unavailable after the rollback, and the new instance will start to incur charges once the original instance is deleted. Data cannot be restored to a point in time when a data dictionary upgrade was in progress. By default, the system searches forward for the most recent available point in time instead. During the period between a data dictionary upgrade and the next full backup, data of the instance cannot be restored to the original instance or an existing instance. When restoring backups, ensure that the data dictionary version of the target instance is the same as that of the source instance.

Procedure

Log in to the management console.
Click in the upper left corner and select a region and project.
Click in the upper left corner of the page and choose Databases > TaurusDB.
On the Instances page, click the instance name to go to the Basic Information page.
In the Instance Information area, click Upgrade under Kernel Version.

Figure 1 Upgrading the minor version on the Basic Information page

Alternatively, go to the Instances page and click Upgrade in the DB Engine Version column.

Figure 2 Upgrading the minor version on the Instances page
In the displayed dialog box, set Scheduled Time and click OK.

Figure 3 TaurusDB minor version pre-upgrade
- Upon submission: The system upgrades the minor version immediately after your submission of the upgrade request. In the Task Center page, click Instant Tasks and view the task progress.
- In maintenance window: The system upgrades the minor version during the maintenance window you have specified. After the operation is complete, on the Task Center page, click Scheduled Tasks and view the information about the upgrade task.
The system will automatically conduct a pre-upgrade check.

In the displayed dialog box, read the message carefully and click OK to proceed with the upgrade.
Figure 4 Pre-upgrade check
After the pre-upgrade is complete, the instance status becomes Pre-upgrade completed, which means no other operations are allowed. On the Basic Information page, click Upgrade under Kernel Version again.

Figure 5 Upgrading the kernel version
In the displayed dialog box, click OK. The system will automatically conduct a pre-upgrade check.

Figure 6 Minor version upgrade
Confirm the check results and click OK.
After the upgrade is complete, the instance status becomes Kernel version upgrade to be confirmed, which means no other operations are allowed. To make the instance available again, go to the Basic Information page and click Apply Upgrade under Kernel Version.

Figure 7 Checking the instance status

Figure 8 Applying the upgrade

Log in to the management console.
Click in the upper left corner and select a region and project.
Click in the upper left corner of the page and choose Databases > TaurusDB.
On the Instances page, select the desired DB instances and click Upgrade in the upper left corner of the list.

Figure 9 Upgrading the minor versions of multiple DB instances at a time

A maximum of 100 DB instances can be selected at a time.
In the displayed dialog box, confirm the information about the DB instances to be upgraded and set Scheduled Time.

Figure 10 Selecting a scheduled time
- Upon submission: The system upgrades the minor version immediately after your submission of the upgrade request. In the Task Center page, click Instant Tasks and view the task progress.
- In maintenance window: The system upgrades the minor version during the maintenance window you have specified. After the operation is complete, on the Task Center page, click Scheduled Tasks and view the information about the upgrade task.
Confirm the information, enter YES in the text box as prompted, and click OK.
- Wait for 2 to 5 minutes and check whether the upgrade has been started for the DB instance. If the upgrade has not been started, check whether the value of rds_global_sql_log_bin is ON and the value of binlog_expire_logs_seconds is at least 86400. If the parameters are not correctly configured, the upgrade cannot be performed.
- If the parameters are correctly configured but the upgrade has not started, it could be due to that the value of rds_sql_log_bin_inconsistent_count is not 0. Wait until this value becomes 0 before proceeding with the upgrade.

Follow-up Operations

Return to the instance list. In the navigation pane, choose Task Center and check the progress of the upgrade task.

If you have selected Upon submission for Scheduled Time:
On the Instant Tasks page, search for "Upgrading a DB instance version" and check the execution progress. Instant tasks cannot be canceled.
If you have selected In maintenance window for Scheduled Time:
On the Scheduled Tasks page, search for the instance ID and check the execution status of the upgrade task.

If the task is in the To be executed state, you can click Cancel to cancel the task.