Maintenance window - Azure Arc-enabled data services

Configure a maintenance window on a data controller to define a time period for upgrades. In this time period, the Arc-enabled SQL Managed Instances on that data controller which have the desiredVersion property set to auto will be upgraded.

During setup, specify a duration, recurrence, and start date and time. After the maintenance window starts, it will run for the period of time set in the duration. The instances attached to the data controller will begin upgrades (in parallel). At the end of the set duration, any upgrades that are in progress will continue to completion. Any instances that did not begin upgrading in the window will begin upgrading in the following recurrence.


An Azure Arc-enabled SQL Managed Instance with the desiredVersion property set to auto.


The maintenance window duration can be from 2 hours to 8 hours.

Only one maintenance window can be set per data controller.

Configure a maintenance window

The maintenance window has these settings:

  • Duration - The length of time the window will run, expressed in hours and minutes (HH:mm).
  • Recurrence - how often the window will occur. All words are case sensitive and must be capitalized. You can set weekly or monthly windows.
    • Weekly
      • [Week | Weekly][day of week]
      • Examples:
        • --recurrence "Week Thursday"
        • --recurrence "Weekly Saturday"
    • Monthly
      • [Month | Monthly] [First | Second | Third | Fourth | Last] [day of week]
      • Examples:
        • --recurrence "Month Fourth Saturday"
        • --recurrence "Monthly Last Monday"
    • If recurrence isn't specified, it will be a one-time maintenance window.
  • Start - the date and time the first window will occur, in the format YYYY-MM-DDThh:mm (24-hour format).
    • Example:
      • --start "2022-02-01T23:00"
  • Time Zone - the time zone associated with the maintenance window.


To create a maintenance window, use the following command:

az arcdata dc update --maintenance-start <date and time> --maintenance-duration <time> --maintenance-recurrence <interval> --maintenance-time-zone <time zone> --k8s-namespace <namespace> --use-k8s


az arcdata dc update --maintenance-start "2022-01-01T23:00" --maintenance-duration 3:00 --maintenance-recurrence "Monthly First Saturday" --maintenance-time-zone US/Pacific --k8s-namespace arc --use-k8s

Monitor the upgrades

During the maintenance window, you can view the status of upgrades.

kubectl -n <namespace> get sqlmi -o yaml 

The status.runningVersion and status.lastUpdateTime fields will show the latest version and when the status changed.

View existing maintenance window

You can view the maintenance window in the datacontroller spec.

kubectl describe datacontroller -n <namespace>


      Duration:    3:00
      Recurrence:  Monthly First Saturday
      Start:       2022-01-01T23:00
      Time Zone:   US/Pacific

Failed upgrades

There is no automatic rollback for failed upgrades. If an instance failed to upgrade automatically, manual intervention will be needed to pin the instance to its current running version, using az sql mi-arc update. After the issue is resolved, the version can be set back to "auto".

az sql mi-arc upgrade --name <instance name> --desired-version <version> 


az sql mi-arc upgrade --name sql01 --desired-version v1.2.0_2021-12-15

Disable maintenance window

When the maintenance window is disabled, automatic upgrades will not run.

az arcdata dc update --maintenance-enabled false --k8s-namespace <namespace> --use-k8s


az arcdata dc update --maintenance-enabled false --k8s-namespace arc --use-k8s

Enable maintenance window

When the maintenance window is enabled, automatic upgrades will resume.

az arcdata dc update --maintenance-enabled true --k8s-namespace <namespace> --use-k8s


az arcdata dc update --maintenance-enabled true --k8s-namespace arc --use-k8s

Change maintenance window options

The update command can be used to change any of the options. In this example, I will update the start time.

az arcdata dc update --maintenance-start <date and time> --k8s-namespace arc --use-k8s


az arcdata dc update --maintenance-start "2022-04-15T23:00" --k8s-namespace arc --use-k8s

Next steps

Enable automatic upgrades of a SQL Managed Instance