Product Redundancy - HP StorageWorks NAS 1500s Installation Manual

Product redundancy

The NAS 1500s is specifically designed to perform file serving
tasks for networks, using industry standard components to ensure
reliability.
Other industry standard features, such as redundant array of
independent drives (RAID) implemented in the hardware and
remote manageability further enhance the overall dependability
of the NAS 1500s.
To ensure redundancy and reliability, the hard drives installed in
the NAS 1500s are configured so that a single drive failure will
not cause data loss or system failure. The NAS 1500s is
configured with dual boot capability. When powered on, the NAS
1500s can boot using a primary OS or a secondary recovery OS.
The primary OS logical drive resides on disk 0 and is mirrored on
disk 1 while the secondary OS logical drive resides on disk 2 and
is mirrored on disk 3. If a single disk failure occurs, the system
will still function off the mirrored disk. If the primary OS
becomes corrupted and un-bootable, the secondary OS is
available for data backup prior to using the Quick Restore DVD
to restore the system to the factory default state.
The data volume is configured as a hardware RAID 5 based basic
partition across all four drives. This ensures redundancy in the
event of a drive failure. The data volume is accessible by both the
primary OS and secondary OS.
Refer to the administration guide for additional information.
NAS 1500s Installation Guide 17