Sun 30 Mar 2008
Data Migration: Bloggers Comment
Posted by John under Startups , Storage and Data Management , VirtualizationI’ve spent a good part of this past week getting ready for Storage Networking World, co-sponsored by SNIA and ComputerWorld, and the I’m-Not-Going-to-Storage-Networking-World event hosted entirely at his own expense by Jon Toigo at a nearby, but semi-secret, location. In honor of the two events, I felt compelled to write about storage. But first, I’ll start with a one-question qualifying quiz.
Small and Medium Business (SMB) Storage Administrator Qualifying Exam
Question: Your “storage system” consists of 25 disk drives that are housed in 8 separate database and file servers. Some of your applications are growing rapidly and require a lot more storage. Others are not growing. In total, you have plenty of available storage capacity, but it sits inside servers that aren’t accessible to the applications that need extra capacity. You want to move to a storage area network, because you’ve heard that all of the storage will then be available to all of the applications and can be managed as a shared pool. You must accomplish the migration of data from the internal drives to a new, blazingly-fast, infinitely-scalable storage area network without interrupting application availability or data access, and without screwing up volume names. From the following, select the answer that most closely describes the correct approach:
- Install EMC’s Invista and watch your troubles disappear.
- Install HDS’s USP and watch your troubles disappear.
- Install IBM’s SVC and watch your troubles disappear.
- Abandon hope. There’s no such thing as a blazingly-fast, infinitely-scalable storage area network that provides non-disruptive data migration.
- Abandon hope. While blazingly-fast, infinitely-scalable storage area networks exist, you can’t get there from here.
- Do nothing. You don’t have enough information.
- This is a trick question. SMB’s don’t have Storage Administrators.
It’s Saturday, and I finally have a little time to read some of my favorite tech blogs. Reading blogs for me is a little bit like taking a slow rambling walk. Starting with the percipient Jon Toigo, blog author of DrunkenData, whose recent post reminded me once again that he is not writing UIAS (Under the Influence of Ad Sales), I followed a comment posted by Chris Mellor of TechWorld, which lead to a post that he had done on IBM SVC vs. HDS USP, which then, after reading the discussion, lead me to Barry Whyte, an IBM Master Inventor, who writes his own storage blog and therein recommended that SMB’s (Small and Medium Businesses) use IBM’s SVC to achieve data migrations.
In all of the discussion about where virtualization should be and who can truly provide non-disruptive data migration in a storage virtualization solution, I’m reminded of a discussion a long time ago with Dave Vellante, former IDC executive, and recent founder of Wikibon. Dave knows a little bit about horse racing, and he tells me there are different horses for different courses. Some horses are good mudders. Others are good on a dry track. Some are good at 5 furlongs. Others on a longer track. I know nothing about horses nor horse racing, but do know a bit about the differences in company requirements, particularly as it relates to such things as computer storage.
In the world of storage, there are, as Dave would say, horses for courses. And when asked the question, “What’s the right storage solution?”, the only correct answer can be “It depends.” Each of the solutions mentioned in the blog posts has a fit. They just don’t fit everywhere. One of my clients, StorMagic, has a very good solution for the SMB market. It was designed specifically for the SMB, in fact, more S than M. It’s not a good solution for large data centers with massive storage requirements. But it scales large enough, and performs well enough, and is affordable enough, for even the smaller end of the SMB market segment. Even with claims of being an appropriate solution for SMBs, if IBM SVC, HDS USP, or EMC Invista show up competing for the same deal, one of the companies is in the wrong deal and wasting their time.
The positioning of StorMagic is for those who would answer #7 to the question above. While the solution is not infinitely scalable, it does enable completely transparent data migration, without screwing up drive letters, and it provides on-the-fly storage upgrade capabilities, at a price small customers can afford.
I hope to see you at SNW or the “Not SNW” event.
April 7th, 2008 at 10:27 am
I found it intersting that none of the three product solutions to your hypothetical challenge could in fact address the requirements. This because you’ve defined that all of the current storage is captive within specific Database or File Servers.
Alas, none of the “virtualization” solutions mentioned offer any means to migrate data out of a server and into external storage.
There are practical solutions, but all of them require host-based migration. Depending upon your Logical Volume Manager, you may be able use it to mirror the ‘local’ data onto an external LUN.
And if your LVM can’t handle this chore, there are other host based migration utilities that operate with near-zero operational or performance impact. For example, EMC offers Open Migrator, which works on practically any version of Windows, Linux or UNIX. It’s pretty simple too - install it, point it at your “old” and “new” storage, and let it go - it will migrate data silently in the background, dynamically adjusting the rate based on I/O workload, and mirroring writes to both devices, just in case something interrupts the process and you have to start over.
And of course, there are others.
So the correct answer to your query, really isn’t #7 - it is actually:
#8. This is a trick question, one that can’t be addressed by external storage, storage appliances or storage networking solutions alone.
April 9th, 2008 at 11:36 pm
Hey Barry,
Thanks for the clarification and the tip. I’ll check out Open Replicator.
John