Snapshot scheduler
Overview
The snapshot scheduler automatically backs up a block storage volume on a cron schedule you configure. It prevents missed manual backups and keeps consistent recovery points. Retention is count-based: keep up to N snapshots, with the oldest deleted automatically when the count is exceeded.
Resource.BlockStorageSnapshotScheduler.CREATEpermission- The target block storage must already exist
Creating a scheduler
- Go to Block Storage > Snapshot Schedulers.
- Click the Create Scheduler button in the top right.
- Configure the following:
| Field | Description |
|---|---|
| Name | Identifier for the scheduler |
| Target block storage | The block storage to back up (pick a zone first; volumes in that zone are listed) |
| Cron expression | Standard cron syntax for the schedule (e.g. 2 4 * * * → daily at 04:02) |
| Maximum snapshots | Number of snapshots to keep (1–100; older snapshots are auto-deleted when exceeded) |
- Click Create.
Cron expressions
The standard 5-field cron syntax (minute hour day month weekday) is used. If you aren't familiar with it, validate the expression on crontab.guru first.
| Expression | Meaning |
|---|---|
0 3 * * * | Every day at 03:00 |
0 */6 * * * | Every 6 hours |
30 2 * * 1 | Every Monday at 02:30 |
0 0 1 * * | The 1st of each month at midnight |
0 0 28 * * | The 28th of each month at midnight |
Retention: maximum snapshots
The ECI snapshot scheduler keeps by count, not by age.
- When the configured Maximum snapshots value (e.g. 7) is exceeded, the oldest snapshot is auto-deleted.
- The allowed range is 1–100.
- If you need an age equivalent: daily × 7 ≈ one week of history.
A higher retention count gives you more recovery points but also more storage cost. Setting between 7 and 30 is typical, depending on workload importance.
Recommended settings
| Workload | Cron | Max snapshots | Result |
|---|---|---|---|
| Always-on server | 0 3 * * * | 7 | About one week |
| ML training checkpoints | 0 3 * * * | 3 | Last 3 days only |
| Long-running project | 0 3 * * 1 | 4 | About one month |
| Quarterly archive | 0 0 1 * * | 4 | About one year |
Backup strategy
The more important your data, the safer it is to layer multiple schedulers rather than try to capture everything in a single scheduler.
The 3-2-1 rule
A widely used baseline:
- 3 copies (one original + two backups)
- On 2 different media (ECI snapshots + external object storage, etc.)
- 1 of them offsite (different zone, different cloud)
ECI snapshots are stored in the same zone, so if disaster recovery matters, regularly restore to block storage in another zone or copy data to object storage.
Multi-tier retention
Running schedulers with different intervals and retention counts together covers both short-term recovery and long-term retention.
| Tier | Cron | Max count | Range covered |
|---|---|---|---|
| Hourly | 0 * * * * | 24 | Last 24 hours |
| Daily | 0 3 * * * | 7 | Last 1 week |
| Weekly | 0 3 * * 0 | 4 | Last 1 month |
| Monthly | 0 3 1 * * | 12 | Last 1 year |
If cost is a concern, skip the hourly tier and run only daily/weekly/monthly.
Managing schedulers
The Block Storage > Snapshot Schedulers list shows:
| Column | Description |
|---|---|
| Name | Scheduler name |
| Cron expression | Configured schedule |
| Target volume | The block storage being backed up |
| Last run | Time of the previous run |
| Next run | Time until the next run (shows Delayed when overdue) |
| Status | Active / Deleted |
Each row's menu offers Edit and Delete. Deleting a scheduler does not delete the snapshots it already produced (delete those separately).
Next steps
- Snapshots: manual snapshot creation and restore
- Block storage: creating, attaching, and resizing disks