To keep your Google Cloud Managed Lustre instances up-to-date, Google Cloud
periodically performs maintenance on them. Maintenance events
include updates to the underlying software or infrastructure.

Maintenance is performed automatically on all Managed Lustre
instances, and by default can occur at any time.

Managed Lustre provides two ways to manage the timing of
maintenance on your instances:

- **[Maintenance policies](https://docs.cloud.google.com/managed-lustre/docs/maintenance#maintenance_policies)**: Configure recurring weekly windows and exclusion periods to control when automated maintenance can occur.
- **[Self-service maintenance](https://docs.cloud.google.com/managed-lustre/docs/maintenance#self-service_maintenance)**: Perform maintenance on demand.

## Maintenance policies

To control when automated maintenance can occur on your instance, you can
configure a *maintenance policy*. A maintenance policy consists of one or both
of the following:

- **Weekly maintenance window**: A recurring one-hour window during the week when Google Cloud is permitted to start maintenance.
- **Maintenance exclusion window**: A period of up to two weeks, optionally recurring annually, where maintenance is blocked.

You can subscribe to receive email notifications of upcoming scheduled
maintenance events. Notifications are sent from 7 to 14 days before an event.
You can also reschedule a maintenance event to start immediately, during the
next weekly window, or at a specific date and time up to 28 days later.

For instructions on configuring policies and rescheduling, see
[Configure maintenance policies](https://docs.cloud.google.com/managed-lustre/docs/maintenance-policies).

## Self-service maintenance

Self-service maintenance lets you upgrade your instance to a newer software
version on demand, as soon as a new version is available. New versions are
available for self-service maintenance up to several weeks before automated
maintenance reaches your instance.

For step-by-step instructions, see
[Perform self-service maintenance](https://docs.cloud.google.com/managed-lustre/docs/self-service-maintenance).

## Impact of maintenance

Maintenance is performed in-place. Your system data, customer-managed
encryption keys, and client mount points are preserved throughout the
maintenance process.

During maintenance, an instance's status transitions from `ACTIVE` to
`UPGRADING` while the upgrade is applied. I/O operations to the instance
temporarily pause. Affected I/O operations resume automatically once
maintenance is complete and the instance returns to `ACTIVE`. Downtime is
typically between 15 to 20 minutes.

## Maintenance notifications and logs

Managed Lustre integrates with
[Cloud Hub](https://docs.cloud.google.com/hub/docs/maintenance) and Cloud Logging to help you
track automated maintenance events across your instances. You can view scheduled
and past maintenance activities in the Google Cloud console, receive email
notifications for upcoming events, or query maintenance records in
Cloud Logging.

For instructions, see
[Maintenance notifications and logs](https://docs.cloud.google.com/managed-lustre/docs/maintenance-notifications).

## What's next

- [Configure maintenance policies](https://docs.cloud.google.com/managed-lustre/docs/maintenance-policies)
- [Perform self-service maintenance](https://docs.cloud.google.com/managed-lustre/docs/self-service-maintenance)
- [Maintenance notifications and logs](https://docs.cloud.google.com/managed-lustre/docs/maintenance-notifications)