Bootable versus non-bootable volumes on 3Engines Cloud[🔗](#bootable-versus-non-bootable-volumes-on-brand-name "Permalink to this headline")
=============================================================================================================================================

Each volume has an indicator called **bootable** which shows whether an operating system can be booted from it or not. That indicator can be set up manually at any time. If you set it up on a volume that does not contain a bootable operating system and later try to boot a VM from it, you will see an error as a response.

In this article we will

> * explain practical differences between **bootable** and **non-bootable** volumes and
> * provide procedures in Horizon and OpenStack CLI to check whether the volume **bootable** or not.

Bootable vs. non-bootable volumes[🔗](#bootable-vs-non-bootable-volumes "Permalink to this headline")
----------------------------------------------------------------------------------------------------

Bootable and non-bootable volumes share the following similarities:

> * **Data storage**: both types can store data (regardless of being bootable or not)
> * **Persistance**: they can be retained even if an instance is removed
> * **Snapshots**: they allow you to create snapshots which represent state of a volume at a particular point in time.

From a snapshot, you can spawn additional volumes so volumes act as a means of both conserving data and transferring of the data.

Bootable volumes usually serve as a boot drive for a virtual machine while non-bootable volumes typically function as data storage only. Bootable volumes can also contain data but one part of capacity will be devoted to the operating system that they contain.

On the other hand, non-bootable volumes can

> * add more storage space to an instance (especially for applications which require lots of data) and
> * separate data from the operating system to make backups and data management easier.

What We Are Going To Cover[🔗](#what-we-are-going-to-cover "Permalink to this headline")
---------------------------------------------------------------------------------------

> * Which volumes appear when creating a virtual machine using Horizon dashboard?
> * Attempting to create a virtual machine from non-bootable volume using OpenStack CLI
> * Checking whether a volume is bootable
> * Checking whether a volume snapshot was created from a bootable volume
> * Modifying bootable status of a volume
> * What happens if you launch a virtual machine from a volume which does not have a functional operating system?

Prerequisites[🔗](#prerequisites "Permalink to this headline")
-------------------------------------------------------------

No. 1 **Account**

You need a 3Engines Cloud hosting account with access to the Horizon interface: <https://horizon.3Engines.com>.

No. 2 **OpenStack CLI client operational**

We assume you are familiar with OpenStack CLI client. If not, here are some articles to get you started: