ApsaraDB for SelectDB lets you update the kernel version of an instance to improve performance, add new features, and fix known issues. When a new version is available, SelectDB notifies your Alibaba Cloud account contacts. Update within six months—instances that remain on an outdated version will experience service interruptions and data loss.
Usage notes
Update your instance within six months of receiving the version update notification. If you do not update the kernel version within six months after receiving the update notifications, service interruptions and data loss occur.
Kernel version updates cannot be rolled back. Once updated, you cannot revert to the previous version.
During an update, you can only view cluster information. Scaling, stopping, and deleting clusters are unavailable until the update completes.
Update impacts
The impact depends on the update type and the update method you choose.
By update type:
| Update type | Impact |
|---|---|
| Kernel version update | Transient connections occur and some read and write requests fail briefly. |
| Database version upgrade | Downtime occurs. Service may be interrupted for about 10 minutes. Schedule during off-peak hours. |
By update method:
| Update method | Cluster availability | Duration | When to use |
|---|---|---|---|
| Rolling update (default) | Available | Brief transient connections | Suitable for most kernel version updates |
| Parallel update | Unavailable | 1–5 minutes | Required for database version upgrades; schedule during off-peak hours |
For database version upgrades, select Parallel Operation Node. The default rolling update may cause communication protocol incompatibilities between versions.
Before you update
To minimize disruption, complete the following checks before starting the update:
If you are performing a database version upgrade, schedule the update during off-peak hours and select parallel update.
Identify whether you want to apply the update immediately or defer it to a maintenance window. See Specify a maintenance window to configure a window in advance.
Update the kernel version
Log on to the SelectDB console.
In the top navigation bar, select the region where your instance 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, configure the following parameters:
Parameter Description Desired Version The kernel version to update to. Update Method When to apply the update. Select Update Now to apply immediately, or Update Within Maintenance Window to apply during your configured maintenance window. Parallel Operation Node The update method for cluster nodes. Not selected by default (rolling update). Select this option to use parallel update. For guidance on which method to use, see Update impacts. Click OK.