Scheduled maintenance in Azure Database for PostgreSQL – Hyperscale (Citus)

Azure Database for PostgreSQL - Hyperscale (Citus) does periodic maintenance to keep your managed database secure, stable, and up-to-date. During maintenance, all nodes in the server group get new features, updates, and patches.

The key features of scheduled maintenance for Hyperscale (Citus) are:

  • Updates are applied at the same time on all nodes in the server group
  • Notifications about upcoming maintenance are posted to Azure Service Health five days in advance
  • Usually there are at least 30 days between successful maintenance events for a server group
  • Preferred day of the week and time window within that day for maintenance start can be defined for each server group individually

Selecting a maintenance window and notification about upcoming maintenance

You can schedule maintenance during a specific day of the week and a time window within that day. Or you can let the system pick a day and a time window for you automatically. Either way, the system will alert you five days before running any maintenance. The system will also let you know when maintenance is started, and when it's successfully completed.

Notifications about upcoming scheduled maintenance are posted to Azure Service Health and can be:

  • Emailed to a specific address
  • Emailed to an Azure Resource Manager Role
  • Sent in a text message (SMS) to mobile devices
  • Pushed as a notification to an Azure app
  • Delivered as a voice message

When specifying preferences for the maintenance schedule, you can pick a day of the week and a time window. If you don't specify, the system will pick times between 11pm and 7am in your server group's region time. You can define different schedules for each Hyperscale (Citus) server group in your Azure subscription.

Important

Normally there are at least 30 days between successful scheduled maintenance events for a server group.

However, in case of a critical emergency update such as a severe vulnerability, the notification window could be shorter than five days. The critical update may be applied to your server even if a successful scheduled maintenance was performed in the last 30 days.

You can update scheduling settings at any time. If there's maintenance scheduled for your Hyperscale (Citus) server group and you update the schedule, existing events will continue as originally scheduled. The settings change will take effect after successful completion of existing events.

If maintenance fails or gets canceled, the system will create a notification. It will try maintenance again according to current scheduling settings, and notify you five days before the next maintenance event.

Next steps