Gana Chandrasekaran

Increasing the Availability of Quorum Provides Extreme Availability for Mission Critical Applications

Blog Post created by Gana Chandrasekaran Employee on Jul 25, 2017

In this update let me talk about Hitachi RAID 800 and how does the Enterprise storage help customers to improve their high availability and providing the new level of meeting RPO and RTO.


The Hitachi RAID 800 Storage is an enterprise class data storage platform for disaster proof storage for mission critical environments. The enterprise storage provides Extreme Availability, Top Performance, and Easy Consolidation for enterprise data. Extreme availability means providing the access to the data anytime, even during extreme difficulties of the situations such as disaster or site failure. In Highly redundant DR scenarios,  RAID 800 uses High Availability (HA) software utilizes a quorum device to provide the authoritative access to the system to maintain HA status. 


What’s New: Online Quorum Migration


This week we are going to discuss about recovering the quorum failure and application still have access to the data with no downtime. Earlier, to replace a Quorum device, the pairs were deleted and data cannot be duplicated during the process. But now the migration of Quorum to a new device can be accomplished without deleting the pairs and data duplication can be maintained. And in case of Quorum failure:


  1.     Continuous symmetrical access to both primary and secondary volume
  2.     Non-disruptive quorum replacement, eliminating replication time! The High Availability pair status maintained
  3.     Data available even in case of quorum and replication link failure
  4.     Data replication is maintained along with the HA




Customer can replace external quorum arrays without impacting the RPO. As mentioned that the recovery is only possible if a data-consistent copy exists, so a maintained the Pair throughout the quorum exchange process makes sure that the data consistent copy exists and the RPO is equal to 0. And through Quorum device provides 100% of data availability and Extreme Availability and provide affordable active-active solutions to the customers.