Xsan overview, 1 san, exasan, and xsan basics, 2 xsan components breakdown – Accusys ExaSAN SW-08 User Manual
Page 52: Xsan overview -1, San, exasan, and xsan basics -1, Xsan components breakdown -1
6. Xsan
User Guide
Page 6-1
6. Xsan Overview
Xsan is Apple Inc.’s workgroup file system for Mac OS X. With the Xsan file system installed, any Mac
with appropriate connectivity can read and write to the same storage volume at the same time.
Starting with Mac OS 10.7, the Xsan file system is included as part of the standard operating system.
There is no longer a need for users to install Xsan software package on OS 10.7 or better.
The descriptions of Xsan in this document are within the context of Accusys ExaSAN only. For a more
generic Xsan configuration, please refer to Apple’s Xsan 2 Administrator Guide.
6.1 SAN, ExaSAN, and Xsan Basics
A SAN (Storage Area Network) is a dedicated storage network that enables multiple computers to access
shared storage. Typical SANs often utilize Fibre Channel technology for the network connection.
ExaSAN is Accusys’ innovation of SAN, which utilizes external high-speed PCIe (Peripheral Component
Interconnect Express) technology to connect computers and storage. It provides the simplicity and fast
speed of a PCIe based SAN solution.
SAN alone does not provide the “file” abstraction, only storage block-level operations. However, with
Apple’s Xsan software on top of SAN, it does provide this abstraction and is known as the SAN file
system.
An ExaSAN-enabled Xsan consists of the following components. See Section 1.1.3, “ExaSAN Compact
Components and Accessories,” for more information.
1. ExaSAN storage systems which provide storage space that is protected against disk failure
2. At least one Mac computer acting as a metadata controller which combines RAID arrays and
presents their storage to Mac clients as volumes that behave like local disks
3. Mac client computers that require accessing shared storage to perform the applications
4. ExaSAN Switch and cables
5. Ethernet Switch and cables
The following illustration shows the hardware components of an ExaSAN-enabled Xsan system.
6.2 Xsan Components Breakdown
Below are more detailed explanations of each Xsan component.