Storage Vendor Humpty Dumpty

10:40 AM -- Lately it seems as if storage vendors are acting like Humpty Dumpty in Through the Looking Glass where he says: "When I use a word, it means just what I choose it to mean, neither more nor less." In just this week's news analysis section of Byte and Switch you can find Nexsan saying it's jumping into the iSCSI market, even though its Beast and Boy arrays have had iSCSI interfaces for years. And you can see EMC using the most common definition inflation of 2009 -- "file-level de-duplication" -- when it adds single instance storage to Celerra.

I hope they treat words as well as Mr. Dumpty, who also said: "When I make a word do a lot of work like that, I always pay it extra."

So, dearest vendors, you can't jump into a market you're already in; there's no such thing as file-level de-duplication (that's single instance storage, as even EMC calls it when talking about Centera); you can't call it revolutionary or the first when you're adding a set of features that a competitor has had for years; and finally -- and most significantly -- you're only a "leading vendor of whatever you sell" if you're No. 1 or 2 in sales.

Thats not to say Nexsan and EMC didn't announce useful additions to their product lines. Nexsan's iSeries appliances, which bear a striking resemblance to SanRad's V-Switches, do add snapshots, mirroring, and replication to the basic feature set of the SAS/SATA Boys and Beasts, which already had just about the best spin-down MAID features on the market.

EMC's Celerra single instance storage and compression will save many users a bunch of disk space while avoiding the creation of storage I/O hotspots that could be de-dupe's Achilles heel for some primary storage applications. Once an administrator turns on de-dupe for a file system, a background process identifies duplicate files using a hash function and inserts intelligent links into the file system to replace the duplicate copies.Only files that have not been accessed for a period of time will be processed, and, in addition to eliminating duplicates, the process will also compress inactive files, including those that are being deduped.

Compared to NetApp's de-dupe (formerly A-SIS), this is a lower-risk, lower-reward mechanism that can't reduce the space occupied by similar files.

Amazingly enough, Windows Storage Server has had single instance storage and file-level compression for years without getting any credit.

— Howard Marks is chief scientist at Networks Are Our Lives Inc., a Hoboken, N.J.-based consultancy where he's been beating storage network systems into submission and writing about it in computer magazines since 1987. He currently writes for InformationWeek, which is published by the same company as Byte and Switch.