ApsaraDB for SelectDB allows you to update the instance kernel version. An update to the instance kernel version enhances instance performance, introduces new features, and fixes issues. If the instance kernel version is outdated, service interruptions and data loss may occur. This topic describes how to update the instance kernel version in the SelectDB console.
Usage notes
If a new kernel version is released, SelectDB sends notifications to the contacts that are specified within the Alibaba Cloud account. You must update kernel version of your instance at the earliest opportunity.
If you do not update the kernel version of your instance to the latest version within six months after you receive the update notifications, service interruptions and data loss occur.
After you update the kernel version of your instance, you cannot roll the kernel version of the instance back to the previous version.
When you update the kernel version of your instance, you can only view the cluster information. You cannot perform operations such as scaling clusters, stopping clusters, or deleting clusters on the instance.
Impacts
During a kernel version update, a transient connection occurs and some read and write requests fail.
During a database version upgrade, downtime occurs and your service may be interrupted for about 10 minutes. We recommend that you upgrade the database version during off-peak hours.
Rolling update: Nodes in the cluster are updated in sequence. In this case, the cluster is still available, but transient connections occur.
Parallel update: Nodes in the cluster are updated at the same time. In this case, the cluster becomes unavailable for 1 to 5 minutes. We recommend that you perform the parallel update during off-peak hours.
Procedure
Log on to the SelectDB console.
In the top navigation bar, select the region in which the instance that you want to manage resides.
On the Instances page, find the instance and click the instance ID.
In the Basic Information section, click Version Upgrade to the right of Minor Engine Version.
In the dialog box that appears, configure the following parameters.
Parameter
Description
Desired Version
The kernel version to which you want to update for the instance.
Update Method
The method that can be used to update the kernel version. Valid values:
Update Now: immediately updates the instance kernel version.
Update Within Maintenance Window: updates the instance kernel version within the maintenance window that you specify. For more information, see Specify a maintenance window.
Parallel Operation Node
Specifies whether to perform parallel update for nodes. By default, rolling update is used.
ImportantFor a database version upgrade, we recommend that you select Parallel Operation Node. The default rolling update may cause communications protocols to be imcompatible between versions.
If you do not select Parallel Operation Node, rolling update is used. You must take note of the following items:
The nodes in a cluster of an instance are updated in sequence. In this case, the cluster is still available, but transient connections occur. We recommend that you use rolling update.
If you select Parallel Operation Node, parallel update is used. You must take note of the following items:
The nodes in a cluster of an instance are updated at the same time. In this case, the cluster becomes unavailable for 1 to 5 minutes.
During the update, the cluster becomes unavailable for a short period of time but the update speed is fast. If you want to update the kernel version in a quick manner, you can use parallel update. We recommend that you perform the parallel update during off-peak hours.
Click OK.