Ananth Adiga

The Agony of Silent Data Corruption: Ensuring Data Integrity for Your Oracle Database

Blog Post created by Ananth Adiga Employee on Sep 20, 2016

     The focus of many of  the sessions and vendor presentations at Oracle OpenWorld this week, #OOW16 are about cloud, IoT, transformation – the common thread in any of these is the data that companies are mining for new value and faster insight.


     There is a lingering threat that is always present and can undermine any data-driven initiative your company may have.


     We have all heard the adverse impact of silent data corruption (SDC) resulting in system and application down time, loss of revenue, lack of regulatory compliance, and perhaps most destructive, loss of customer’s trust. Data integrity is very critical for any organization be it for business critical, transactional data or data at rest and is the most important aspect of data management life


     Data integrity measures are means to mitigate SDC and ensure data is accurate and consistent from the point of generation i.e. the application  through the data path to its destination i.e. the disk drive. In the data path are several hardware and software components: OS, IO controller/HBA, SAN, storage array controller and the disk drives that can introduce data corruption which may go undetected until the time it is retrieved. 


     While  there are several generic methods including Error-correction code (ECC) , Cyclic redundancy check (CRC) and vendor-specific data integrity check implementations at the component layer and  across multiple component layers to detect and correct SDC at every stage of the IO path, it is not a complete  solution,  since there are gaps  from  the application to the disk  where SDC can occur. To achieve end-to-end (E2E) data protection there has to be  different integrity check schemes,  handoffs  throughout  the entire IO path that  can detect  data mismatch at any component level, pass the error through the layers to abort the IO and prevent corrupt data writes.  SDC detection must  also be performed in the reverse order   for read operations. 

The industry standard specification SCSI Protection Information /Data Integrity Field Model (T10  PI/DIF) and Data Integrity Extensions (DIX)  allows multiple components to  exchange and verify protection information for E2E detection and prevention of SDC. Solution implementations that conform to T10 PI-DIX are now available from HDS that cover SDC gaps in the IO path to deliver robust E2E data integrity assurance for Oracle databases.


     Hitachi Storage Virtualization Operating system (SVOS) now supports T10 PI-DIX. SVOS is the software core at HDS storage and converged solutions. The feature is available in SVOS 6.3.1 for the Gx00 series and SVOS 6.4 for Hitachi VSP G1000. The T10 PI-DIX support in the Hitachi storage  solutions also covers our Data Protection solutions including Hitachi TrueCopy, Hitachi Universal Replicator, Hitachi ShadowImage, Volume Migrator and Global Active Device features.


     Hitachi Data Systems in collaboration with Cavium Inc. and Oracle Corporation provides E2E protection against silent data corruption that conforms to T10 PI specification. This implementation is supported  on Oracle Linux 6.5 update 5 UEK  kernel , Qlogic Secure Flex  enhanced Gen 5 HBA 2672 with  firmware 7.04.01 and above.  On the Storage it requires simple administrative steps  to enable T10 PI  for ports and logical devices . Host level command interface is also available to enable the T10 PI feature.   

With the inclusion of this critical feature HDS stays committed to ensuring our customers, and THEIR customers, have the protection their valuable data needs, investment protection for the infrastructure that runs the critical apps and as we continue to work with partners like Oracle with their Oracle Database, Oracle Linux and Oracle VM ecosystem, to  extend the value proposition that customers cannot ignore. 


     Both operation IT leaders, Database administrators and storage administrators, and business leaders, CIOs, CTOs and the company itself, can rest assured their data is safe, secure and available.   

     You can see our solutions at the HDS booth #1901 in the Oracle Linux showcase @ Oracle OpenWorld this week.

     The HDS team is blogging all week from #OOW16 on the HDS Community Oracle site, so please check in with us often and join the conversation.