Hitachi STORAGE 9900 User Manual
Page 36
•
Dual data paths and dual control paths connecting every component
•
Mirrored cache for all write data instead of single image cache
4
•
IBM
®
Geographically Dispersed Parallel Sysplex
™
(GDPS
™
) support
•
Hitachi TrueCopy
™
software combined with Hitachi ShadowImage
™
software for
disaster recovery
•
NanoCopy
™
technology to provide point-in-time copies without requiring
quiescence of databases or applications
•
High-availability, custom-designed disk drives
•
Hi-Track
®
“call-home” capability to notify the Hitachi Data Systems support
center quickly of any incident that may affect availability
Figure 21 highlights some of the many advantages in high-availability design that the
Lightning 9900 V Series has over other enterprise storage products.
Open Systems High-availability Middleware Support
Open-systems server vendors and third-party software vendors, such as VERITAS
Software, have developed a class of software known as “high-availability middleware” to
help reduce downtime by automatically detecting faults and recovering data services on a
redundant set of hardware. Without high-availability middleware, time is lost while a fault
goes undetected. Once the fault is detected, a diagnose/repair/replace action must take
place before data-service recovery can begin. High-availability middleware can begin an
automated recovery process immediately on the redundant hardware. The recovery process
without high-availability middleware involves time-consuming and error-prone manual
operations, which may include resetting the SCSI bus, restarting drivers, reassigning IP
addresses, recovering and restarting applications and transactions, and even rebooting.
Hitachi is the only major
supplier of enterprise
class storage systems with
a 100 percent
availability guarantee.
Hitachi Data Systems
26
4
Some competitive products do n o t have dual cache like the Lightning 9900 V Series
systems. If there is an unrecoverable error in cache, there is no duplicate backup copy. With
these products there is an increased risk of lost data, especially if the loss occurs in the
h a rd w a re status area. The Lightning 9900 V Series systems do not have this problem since all
status areas and write data are duplexed.
The recovery process
without high-availability
middleware involves
time-consuming and
error-prone manual
operations.
Figure 21 - The
Lightning 9900 V Series
offers a far more
complete range of
availability protection
than competitive
products.