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 the updates in each kernel version, see TaurusDB Kernel Version Release History.

Upgrade Scenarios

Depending on the kernel version, upgrading a minor version involves three scenarios.

**Table 1** Kernel version upgrade scenarios
Upgrade Scenario	Upgrade Path	Description
Scenario 1: kernel version < 2.0.51.240305	Due to the large version gap, first upgrade the kernel version to 2.0.51.240305 or 2.0.51.2403** (subject to the version displayed on the console). After this upgrade is successful, perform a minor version pre-upgrade and a minor version upgrade in sequence.	The entire upgrade process takes about 5 minutes per node. The upgrade will trigger two primary/standby switchovers, which may interrupt workloads for about 30–90 seconds. To minimize the impact of the upgrade, perform the upgrade during off-peak hours, or ensure that your application has an automatic reconnection mechanism.
Scenario 2: 2.0.51.240305 ≤ kernel version ≤ 2.0.51.2403**	Perform a minor version pre-upgrade first. After the pre-upgrade is successful, click Upgrade again to perform the minor version upgrade. The following operations use this upgrade method as an example.	The entire upgrade process involves the upgrade of the data dictionary, which takes a long time. Before the upgrade, check the configurations of the following parameters: rds_global_sql_log_bin must be set to ON. The value of binlog_expire_logs_seconds must be greater than or equal to 86400. default_collation_for_utf8mb4 must be set to utf8mb4_0900_ai_ci. For details, see Modifying Parameters of a DB Instance. Minor version pre-upgrade A temporary instance is created for verifying the upgrade process. A DR instance is created for version rollback. During this process, the original instance is not rebooted and workloads are not interrupted. For an instance with a small amount of data, this process takes about 15 minutes. For an instance with a large amount of data, this process takes about 15 minutes plus an additional 20 minutes for every 1 TB of data. For example, this process takes at least 35 minutes for an instance with 1 TB of data. Minor version upgrade Your instance will be rebooted during the upgrade and workloads will be interrupted. The entire upgrade process takes 15–20 minutes, including a brief interruption of 1–2 minutes. Perform the upgrade during off-peak hours. The synchronization delay between the original and DR instances is checked during the upgrade. To prevent upgrade failures caused by excessive delay, ensure that the minor version upgrade does not overlap with the pre-upgrade time. During the upgrade, the original instance will be temporarily set to read-only until data synchronization between the original and DR instances is complete. In scenarios involving large transactions, the read-only duration may last longer than expected, which can cause the upgrade to fail.
Scenario 3: kernel version ≥ 2.0.54.240600	Clicking Upgrade will directly trigger a minor version upgrade to the latest version.	The entire upgrade process takes about 5 minutes per node. The upgrade will trigger two primary/standby switchovers, which may interrupt workloads for about 30–90 seconds. To minimize the impact of the upgrade, perform the upgrade during off-peak hours, or ensure that your application has an automatic reconnection mechanism.

Depending on the execution time, a minor kernel version upgrade can be performed in two ways.
- Upon submission: The system upgrades the minor version upon your manual submission of the upgrade request.
- In maintenance window: A scheduled upgrade task is generated. 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.

Constraints

**Table 2** Constraints
Phase	Constraints
Before the upgrade	If the rds_global_sql_log_bin parameter is set to ON, you need to connect to the database and run the following command to check whether binlog is enabled for all threads: select @@session.rds_sql_log_bin_inconsistent_count; rds_sql_log_bin_inconsistent_count specifies the number of users whose sql_log_bin setting differs from the rds_global_sql_log_bin setting. If the command output is 0, binlog has been enabled for all threads, and all statements can be recorded in binlogs. If the command output is not 0, perform the following operations: If you connect to the DB instance through DAS, view warnings on the Messages tab page of the executed SQL statements. If you connect to the DB instance through the mysql client, run the following command to check the IDs of the threads that binlog has not been enabled for. The statements executed in the queried threads may not be recorded in binlogs. show warnings; 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	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 there are large transactions in your instance, switchovers during the upgrade may take longer than expected. If there are large transactions in your instance, setting the instance to read-only during the upgrade in scenario 2 (2.0.51.240305 ≤ kernel version ≤ 2.0.51.2403**) will fail. When you upgrade the minor version of an instance, minor versions of read replicas (if any) will also be upgraded. During the upgrade, the read replicas will reboot. To minimize the impact, perform the upgrade during off-peak hours. 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. 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	Scenario 2: If the upgrade fails, the instance will be rolled back to a previous version and its data will be restored to a new instance named original_instance_name_copy. The original instance will become unavailable after the rollback. If the original instance is not deleted, it continues to be billed, but the new instance does not generate any fees. The new instance is only billed after 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 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 data is restored from a backup, the versions of the source and destination instances must adhere to the following constraints: If the source instance's kernel version is 2.0.54.240600 or later, the destination instance's kernel version cannot be earlier than 2.0.54.240600. If the source instance's kernel version is earlier than 2.0.54.240600, the destination instance's kernel version cannot be 2.0.54.240600 or later.

Checking Version Information

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

Upgrading a Minor Version

Log in to the TaurusDB console.
Click in the upper left corner and select a region and project.
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, select a scheduled time and click OK.

Figure 3 TaurusDB minor version pre-upgrade
- Upon submission: The system upgrades the kernel version immediately after you submit the upgrade request.
- In maintenance window: The system upgrades the minor version during the maintenance window you have specified.
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 another pre-upgrade check.

Figure 6 Minor version upgrade
Confirm the check results and click OK.
If you have enabled operation protection, click Send Code in the displayed Identity Verification dialog box and enter the obtained verification code. Then, click OK.

Two-factor authentication improves the security of your account. For details about how to enable operation protection, see Identity and Access Management User Guide.
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 TaurusDB console.
Click in the upper left corner and select a region and project.
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 once

A maximum of 100 DB instances can be selected at once.
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 maintenance window: The system upgrades the minor version during the maintenance window you have specified.
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.
If you have enabled operation protection, click Send Code in the displayed Identity Verification dialog box and enter the obtained verification code. Then, click OK.

Two-factor authentication improves the security of your account. For details about how to enable operation protection, see Identity and Access Management User Guide.

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.

For details, see Viewing a Task.

FAQs

Why Is My Instance in the Kernel version upgrade to be confirmed State After an Upgrade?

If your instance is in such a state, there is a temporary DR instance. This temporary instance is running the version before the upgrade and is used for compatibility rollback in extreme scenarios. Check whether workloads are normal. If they are, click Apply Upgrade to release the temporary instance. Once the temporary instance is released, your instance cannot be rolled back to the original version.

When your instance is in such a state, you cannot modify parameters or promote a read replica to primary on the console.