Apple Xsan 1.x User Manual

Page 38

Chapter 3

Deployment Examples

What levels of performance do your users require?
Performance is critical in this example. The primary concern is avoiding dropped video
frames. We were guided by this requirement when we selected the number of Xserve
RAID systems for the configuration. To make sure we get the best performance out of
the file system itself, we’ll keep metadata separate from other network traffic (such as
Internet access and directory transactions) by using two Ethernet networks and by
storing the metadata for each volume on its own storage pool and RAID controller.

How important is availability?
High availability is important, so the configuration includes a standby metadata
controller. All the data LUNs are set up as 6-drive RAID 5 arrays with a hot spare drive
on each controller.

Which storage pools make up each volume?
Each volume consists of just two storage pools, one for metadata and the other for user
data. Data LUNs are composed of 7-disk RAID 5 arrays for maximum performance.

Where do you want to store file system metadata and journal data?
Because we want the best possible performance from the volumes, we store the
metadata storage pool for the two volumes on separate RAID controllers.

2-disk RAID 1

7-disk RAID 5

DV pool, DV storage volume

DV pool, DV online volume

Audio pool, DV online volume

Metadata pool, DV online volume

Metadata pool, DV storage volume