Datasheet

11
Technology Overview
Xsan
File system journaling
Xsan is a journaled file system that can be recovered in seconds in the event of a
server failure. Journal data includes a record of file system transactions, eliminating the
need for time-consuming integrity checks after an unplanned shutdown of the entire
network or of the metadata controller. Your storage can be back online immediately.
Volume Management
Flexible volume management capabilities enable you to maximize the efficiency of
your storage resources. Xsan makes it easy to target data types to specific classes of
storage for optimal storage performance—for example, assigning all uncompressed
HD video files to one high-performance storage pool. You can then combine pools
into volumes for simplified management. Xsan also makes it easy to expand your
storage resources as your data needs grow: You can add LUNs and storage pools and
create new volumes—without interruption in service. The downtime to grow a volume
is typically just seconds.
Storage pools and SAN volumes
Storage pools allow you to aggregate storage resources with similar attributes. Using
Xsan administration tools, you can pool LUNs with identical size, performance, and
data protection properties. Different types of storage pools can then be combined
into the same volume.
For example, you can create one storage pool of RAID 5 LUNs and another pool of
RAID 1 LUNs. The RAID 5 LUNs provide high performance and good capacity with
some protection. The RAID 1 sets use redundant drives for the highest level of pro-
tection. By creating a SAN volume from these two different pools, you can achieve
a good balance between speed and protection in a single volume. This allows the
administrator to choose how to manage storage, without having to involve the user.
A storage pool can contain up to 32 LUNs and a volume can contain up to 512 LUNs.
Storage pool
Storage pool
1
1
Volume
Xserve RAID
Build Xsan volume in Xsan Admin.
Build RAID set in RAID Admin.
Multiple LUNs
LUN
Volume Management