Use the following procedure to configure automatic snapshots of a filesystem, LUN, or project and set a retention policy for those snapshots.
Automatic snapshots can be taken half-hourly, hourly, daily, weekly, or monthly and are named .auto[-<snaplabel>]-<timestamp>. In the Creation column of the Snapshots list, times are displayed in the local (client browser) time zone. However, times are stored and executed in UTC format, without regard to such conventions as daylight saving time. For example, a snapshot scheduled for 10:00 a.m. PST (UTC-8) is stored and executed at 18:00 UTC, and this is the time that will appear as the timestamp in the snapshot name.
Automatic snapshots can be set on a project or a share, but not both. Otherwise, overlapping schedules and retention policies would make it impossible to guarantee both schedules. Removing an interval, or changing its retention policy, will immediately destroy any automatic snapshots not covered by the new schedule. Automatic snapshots with clones are ignored.
For half-hourly or hourly snapshots, you can choose how many minutes after the half-hour or hour the snapshot is taken. For daily snapshots, you can choose the hour and minute the snapshot is taken, and for weekly or monthly snapshots, you can specify the day, hour, and minute.
Automatic snapshots can be kept forever (except for half-hourly and hourly snapshots, which are capped at 48 and 24, respectively), or they can be limited to a certain number. When the number of snapshots exceeds the number you have specified here, the oldest snapshots will be deleted first.