Dot Hill With Four New Patents

Dot Hill Systems Corp. announced the addition of four new patents to the company’s technology portfolio, upping the company’s intellectual property total to 71 patents granted by the United States Patent and Trademark Office.

"These four patents serve as validation of Dot Hill’s technical expertise and our ability to produce highly relevant technology solutions to real-world business problems," said Jim Kuenzel, senior vice president of engineering at Dot Hill Systems. "Our customers should not have to worry about their data. This is why our engineering team is on a perpetual quest to improve data reliability and solve the operational efficiency challenges storage administrators face on a daily basis."

Dot Hill’s newest innovations address the need for high data reliability and efficiencies in storage operations. The first of the four patents describes inventions to improve how data in a RAID system is rebuilt when a corruption error occurs. While RAID systems from other vendors replace bad blocks using data from the same, failing drive, U.S. patent 7,774,643, Method and apparatus for preventing permanent data loss due to single failure of a fault-tolerant array, describes a more reliable approach. This technology ensures that other sources, never the corrupted drive, are used to rebuild the blocks. This method is not only more reliable, but also improves performance because only the bad block is reconstructed, as opposed to the entire stripe containing the bad block, as in most other RAID methods.

The second patent describes innovations to increase the reliability of Dot Hill’s storage systems, and is implemented in the 2000 Series and 3000 Series systems. U.S. patent 7,788,541, Apparatus and method for identifying disk drives with unreported data corruption, describes technology that allows the RAID controller to identify certain kinds of disk drive problems that are not reported as failures by disk drives. This innovation addresses a potential risk of traditional RAID storage. In some instances, unreliable data goes undetected and is read from storage devices, resulting in application failures, wrong data or incorrect status presented to servers and clients. This innovation provides users with more granular detection means, resulting in higher data reliability.

The inventions in the third and fourth patents both offer storage administration efficiencies and improved system responsiveness. Patent 7,783,603, Backing store reinitialization method and apparatus, describes an improvement to Dot Hill’s AssuredCopy volume copy software and is implemented on Dot Hill 2000 and 3000 Series storage arrays. It allows system administrators to reinitialize a storage volume in one step after a snapshot deletion command is issued to the controller when all snapshots are already either being deleted or marked for deletion. While this was previously a serial operation where one snapshot was deleted at a time, the patented new method saves time and quickly readies the system for new snapshots.

The company’s fourth patent describes a method that makes it possible to write to the Master Volume (storage file system) even when the Master Volume is being copied on Dot Hill 2000 Series and 3000 Series arrays. Previous to this innovation, a system administrator might copy the Master Volume for security or reliability reasons and find that the file system would be unavailable. Updates to the Master Volume would be put on hold until the copy was completed, to ensure the integrity of the copy. This would essentially make the storage unavailable until the operation was complete. The innovation described in U.S. patent 7,783,850, Method and apparatus for Master Volume access during volume copy, ensures the storage is fully available, and the Master Volume can be updated simultaneously during the copy process.