Synnefo

.. _archipelago:

Volume Service (archipelago)

^^^^^^^^^^^^^^^^^^^^^^^^^^^^

Introduction

============

Every Volume inside a VM can be thought of as a linearly addressable set of

fixed-size blocks. The storage of the actual blocks is orthogonal to the task of

exposing a single block device for use by each VM. Bridging the gap between the

VMs performing random access to Volumes and the storage of actual blocks is

Archipelago: a custom storage handling layer which handled volumes as set of

distinct blocks in the backend, a process we call volume composition. For the

actual storage of blocks we are currently experimenting with RADOS, the

distributed object store underlying the Ceph parallel filesystem, to solve the

problem of reliable, fault-tolerant object storage through replication on

multiple storage nodes. Archipelago itself is agnostic to the actual block

storage backend. 

Archipelago is under active development and will be available soon.