Cloud Block Storage Tutorial

Welcome to Cloud&Heat and our Cloud Block Storage Tutorial!


Prerequisites and Goal

The purpose of this tutorial is to help you getting started using Cloud Block Storage. After completing this tutorial you will be able to:

  • Create persistent block storage,
  • Attach and detach block storage to and from a running VM,
  • Make a snapshot of the block storage, and
  • Delete the block storage.

You will NOT learn how to start a VM and how to access it. In fact, this tutorial assumes you have read the introductory Cloud Compute Tutorial, and are familiar with how to configure the Cloud&Heat Dashboard and launch VMs, and how to access them.

Apart from Cloud Block Storage, Cloud&Heat also offers other persistent storage solutions. To learn more about these options, please read Selecting Persistent Cloud&Heat Storage.


Introduction

The kind of block storage we use for Cloud Block Storage is called volumes, and behave much like NAS volumes. Data on a volume is stored persistently and replicated three times. Volumes can be moved between instances and thus, in case one instance terminates, the data can easily be made accessible from another instance. In comparison, all data saved directly on the disk of a virtual machine (VM) instance, as opposed to on a volume, is ephemeral and will be lost in case the VM is terminated. Such data cannot be recovered, and therefore volumes should be used for storing data which should survive the termination of an instance.

The data stored in Cloud Block Storage is encrypted at rest, but to achieve maximum security we recommend additionally encrypting your data.


Outline of the Tutorial

To successfully use volumes for storing your data, you need to perform the steps of the tutorial in the order given by the outline:

  1. Create a volume.
  2. Attach it to a running VM from the dashboard.
  3. Attach it to the VM from the VM.

Later, you might also want to detach the volume from the VM, make a snapshot of it, or delete it.