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Snapshots are an important tool for backing up instances before doing work on them, or to create new instances based on another existing instance.

Creating a Snapshot

To snapshot an existing instance, first ensure that you have enough volume storage for the snapshot. From the dashboard, under the "Compute" section of the menu bar, select "Overview" to see how much volume storage you have remaining. You will require enough volume storage both for the snapshot itself, and for a new instance built from the snapshot (if that is what you wish to do with the snapshot). When creating a snapshot of an instance, a copy is made of every volume currently attached to that instance. So (for example) if your instance has a 20GB root disk volume plus an additional 100GB storage volume attached, you would need at least 120GB for the snapshot to copy both the root disk and storage volumes; if you intend to use the snapshot to create another instance, you will need another 120GB on top of that again.

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