A maintenance window is a designated timeframe during which planned maintenance tasks, such as operating system updates, security patches, and infrastructure upgrades, are performed automatically to ensure the reliability, security, and performance of the TiDB Cloud service.
During a maintenance window, the maintenance is executed on TiDB Dedicated clusters one by one so the overall impact is minimal. Although there might be temporary connection disruptions or QPS fluctuations, the clusters remain available, and the existing data import, backup, restore, migration, and replication tasks can still run normally.
By configuring the maintenance window, you can easily schedule and manage maintenance tasks to minimize the maintenance impact. For example, you can set the start time of the maintenance window to avoid peak hours of your application workloads.
During a maintenance window, some operations are allowed, while some are not.
- SQL operations
- Create clusters
- Delete clusters
- Create backup tasks
- Restore clusters
- Access cluster pages
- Modify, pause, or resume clusters
- Change security settings in the TiDB Cloud console
- Create private links or configure VPC peering
- Create import tasks, migration jobs, or changefeeds
- Scale specifications of migration jobs or changefeeds
To avoid potential disruptions, it is important to be aware of the maintenance schedules and plan your operations accordingly.
For every maintenance window, TiDB Cloud sends four email notifications to all project members at the following time points:
- Two weeks before a maintenance window starts (excluding urgent maintenance tasks)
- 72 hours before a maintenance window starts
- The time when a maintenance window is started
- The time when a maintenance window is completed
Regular maintenance ensures that essential updates are performed to safeguard TiDB Cloud from security threats, performance issues, and unreliability. Therefore, the maintenance window is enabled by default and cannot be disabled.
If a maintenance window is planned, the default start time of the window is 03:00 Wednesday (based on the time zone of your TiDB Cloud organization) of the target week.
You can modify the start time to your preferred time or defer maintenance tasks until the deadline as follows:
Log in to the TiDB Cloud console.
Click in the lower-left corner, switch to the target project if you have multiple projects, and then click Project Settings.
On the Project Settings page of your project, click Maintenance in the left navigation pane.
If any maintenance tasks are displayed, check the descriptions, scheduled start time, and deadline. The maintenance tasks will start at the designated time.
If there is no maintenance data, it means no maintenance task is scheduled recently.
(Optional) Click to modify the start time of the maintenance window. Note that the maintenance will be performed at the specified start time only if there is a maintenance window planned for that week.
To defer the start time of a scheduled maintenance task, click Defer in the Action column and change it to the next feasible maintenance window before the deadline.
If you need to defer the maintenance task beyond the deadline, contact TiDB Cloud Support for assistance.
What are maintenance tasks?
Maintenance tasks typically include operating system updates, security patches, and infrastructure upgrades.
Can I disable a maintenance window?
No. The maintenance window is enabled by default and cannot be disabled. You can modify the start time of the maintenance window or defer a maintenance task to 2 to 4 weeks until the deadline. For more information, see View and configure maintenance windows.
How long does a maintenance window last?
It depends. For each project, maintenance is executed on eligible TiDB clusters one by one. The duration of maintenance varies depending on the number of clusters, cluster data size, and the maintenance tasks to be performed.
Will maintenance tasks be performed on clusters in any status?
No. TiDB Cloud checks the cluster status before performing a maintenance task on a cluster.
- If the cluster is in the Creating or Paused status, maintenance tasks are not required.
- If the cluster is running an automatic or manual backup, the maintenance will be delayed and triggered until the current backup is successfully completed. Note that for clusters with large data volumes, the backup process might take a long time, such as 12 hours. To minimize the impact on the clusters, it is recommended to carefully set the start time for backups and the maintenance window.
- If the cluster is in any other status, the maintenance tasks will start as scheduled.