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Storage
This chapter discusses the framework for storage abstractions. It describes the way physical storage hardware of various kinds is mapped to VMs, and the software objects used by the XenServer host API to perform
Storage Overview
This section explains what the XenServer storage objects are and how they are related to each other.
Storage Repositories (SRs)
XenServer defines a container called a storage repository (SR) to describe a particular storage target, in which Virtual Disk Images (VDIs) are stored. A VDI is a disk abstraction which contains the contents of a virtual disk.
The interface to storage hardware allows VDIs to be supported on a large number of SR types. The XenServer SR is very flexible, with
Each XenServer host can use multiple SRs and different SR types simultaneously. These SRs can be shared between hosts or dedicated to particular hosts. Shared storage is pooled between multiple hosts within a defined resource pool. A shared SR must be network accessible to each host. All hosts in a single resource pool must have at least one shared SR in common.
SRs are storage targets containing virtual disk images (VDIs). SR commands provide operations for creating, destroying, resizing, cloning, connecting and discovering the individual VDIs that they contain.
A storage repository is a persistent,
CLI operations to manage storage repositories are described in the section called “SR commands”.
Virtual Disk Images (VDIs)
Virtual Disk Images are a storage abstraction that is presented to a VM. VDIs are the fundamental unit of virtualized storage in XenServer. Similar to SRs, VDIs are persistent,
Physical Block Devices (PBDs)
Physical Block Devices represent the interface between a physical server and an attached SR. PBDs are connector objects that allow a given SR to be mapped to a XenServer host. PBDs store the device
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