# What is a Volume

A PMO volume is a logical storage volume allocated on a centralized persistent block storage device. A volume represents a logical area on that storage device.

Any data that is stored on a volume is persisted until it is erased from the volume.

A volume must be mounted on a virtual machine instance for it to be accessible within the guest operating system of that VM.

A volume can be created from a volume snapshot, another volume, an image, or as an empty / blank volume.

Volumes can be bootable or non-bootable. A bootable volume can be used to boot a VM from the persistent data store.

Volumes can be attached to instances for persistent block storage. Unless otherwise specified, the data on the volume persists even after the instance is destroyed.


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