Greg Secrist on ILM, and everything else under the "SUN"

iSCSI and ILM?

So we all agree that ILM is a concept, not an actual technology ... right? But, we all agree that it is how we use technology and solutions to make ILM really work ..... right?  Glad you're with me so far.

 I've been working on a project where the customer is interested in ILM. To them, however, it is also about data mobility. Sure, we can set things up to place the right data, at the right storage location, at the appropriate time; all based on data / information  business characteristics.  That is data placement and optimization by moving data between storage tiers.  What about sharing that data among multiple users, especially when the data has some abnormal traits?  Like, a 2TB dataset with a mix of large (50GB) files and lots of really small files. (say, 25 million files!)  Get the picture?

The kicker is that all of this data has to be accessible together.  The challenge of course is not just sharing it among different users, but how I protect it from loss or corruption?  Traditional  backup is out of the question for obvious reasons.

 Here is what I proposed. Pretty cool stuff.  Because the data is Windows data, it must be readable and mountable by Windows hosts.  The data only needs to be used  by a single Windows system at any given time.  So, I had them create a 2TB zfs volume, and present it as an iSCSI volume. (yes, Solaris is a totally free and full featured iSCSI target platform).  This is over their 10GigE network.  The Windows boxes mount this iSCSI share and format it as NTFS. To Windows, it looks like a basic disk.

Here is the really cool part. Under the hood, it is zfs volume. I can snapshot the volume, replicate the volume using zfs send, and do complete volume copies, then present to another Windows box.  No copying of the complex file level structure. It is all done at the zfs volume layer.  This gives me a way to protect, share, copy, and move a very complex data structure without ever touching the file system.  Efficient, fast, and ..... free.   No expensive license costs addons for the iSCSI feature, or the replication feature.  I can do this on Sun X4540 array for about $1 per GB in total costs. That is because I'm only paying for the server/storage node and software support. No markup for the really cool Solaris features.  Best of all ... it works great!   

Posted at 10:26AM Sep 21, 2008 by Greg Secrist in Sun  |  Comments[1]

The "Egg Basket" Idiom and Data Protection

My wife has several Longaberger baskets in a variety of shapes and sizes.  She uses some for floral arrangements, one for toting casseroles to the occasional dinner party, and others just for decoration.  She has baskets for different stuff.  If we still needed to carry our eggs from the hen house to the kitchen, I'm sure she would buy two more; one for the left hand and the other for the right hand.  Why? In case one slipped or tipped during the walk back, we'd at least have half of our eggs instead of none at all. 

Ok, you know where I'm going with this.  The proverbial "don't put all your eggs in one basket" is the perfect idiom to describe what not to do when trying to protect your data from loss or interruption.   It is a simple analogy, but I can't tell you how many times I see IT fail to apply it practically.

I've seen "tape only" backup systems being used as the sole container for data copies that are routinely recalled every time a user deletes an email or spreadsheet.   This means that every time an email mailbox is restored, a tape is mounted and read. Multiply this by dozens or hundreds of recalls a day and you can start to see why some recalls eventually fail.  (Especially when the system is architected with primarily capacity tape technology like LTO)  The result:  tape gets a bad rap because it is deemed "unreliable" and troublesome. 

I've seen customer's buy into the "hype" and trade out their tape-based backup systems for a VTL.  (An "all disks" egg basket)  Within a year, I see them scratching their heads why it is costing them 5-times as much to continue storing their data?  In one particular case, I saw an EMC EDL (EMC's VTL appliance) go down and fail to roll-over to the other VTL engine.  What happened?  This customer's entire backup system was down for several days, with some loss of data.  Why did it fail???? Over provisioning of virtual tapes and overload of the system.  The result: the customer is burned by VTL and it quickly becomes suspect for reliability.  Bet they wished they had a "last resort" copy of their data sitting out there on a tape somewhere!

This why you don't put all your data "eggs" in one data protection basket.  This is why I evangelize a tiered data protection architecture.  Call it tiers of defense.  If you only have a single wall around the castle, you are royally hosed if the enemy gets through a breach.  If you have an outer wall, a moat, and a final wall, you probably won't have to depend on that final wall. But it is nice to have just in case. 

Tape is your last line of defense that should be written too often and read from only when all other copies don't work.  Your first line of defense should be multiple point-in-time copies of your data on disk. The copy can be a database dump, volume split, snapshot, continuity volume, or any combination of these.  At the same time, you should make a point to make a "copy of the copy" to tape, just in case.  That makes tape your last line of defense that should prove reliable because you only go to it on occasion, not every time, every day. 

Think of it as splitting your eggs between baskets; the first being a Longaberger and the 2nd being a 9.99 special from Crate&Barrel.   

Posted at 10:46PM Jun 07, 2008 by Greg Secrist in Sun  |  Comments[1]

What the economy and tape have in common ...

With all the bad press lately about the state of the US economy, it got me thinking about tape storage. I know, I know .... "how on earth did you make that leap?", you ask.  The answer is simple.  If you hear it from others enough, you start to believe it to be so.  No, this isn't going to be some "paranoid" rant about the hidden agenda of our news media.  I am simply making an observation and connection.  The media reports and repeats what sells.  They know that the average listener will perk up and pay attention when the content is "urgent" or may directly impact their well being.  That is why negative content outweighs the positive content 10 to 1. (based on loose statistical research)

So, what is the connection between the economy and tape?  The negative message.  With regard to the economy, if people hear it enough, they start to believe it worse than it may be.  It affects their attitudes about spending, investment risks, etc.  That snowballs into driving actual changes in the economy that the media continues to report.  Get the picture?  The same thing has happened with the role and value of tape in the data protection stack.  Certain companies have done a great job at marketing and reporting that "tape is dead".  They focus on telling stories involving the woes of tape, and drop subtle marketing jives that disk will solve everything.  The final link to my "economy" analogy is the costs of storage. The final jab is that disk is now cheaper than tape, making it a "no brainer".    You hear this at industry events, read about it in tech journals and periodicals, and get white papers sent to your inbox; all telling you that "tape is dead" and you better change before it is too late. 

The more rational message (and the reality) is that tape is still a valuable, affordable, and reliable data repository in the whole tiered storage model.  Tape storage plays an important part in a true ILM approach.  However, like your doctor tells you, "drink and eat in moderation."   The same applies to tape storage.  Use tape the way it is meant to be used, augmented by disk storage the way it is supposed to be used.  It is not an all-or-nothing technology.  That is why we call it a tiered storage model, with tape having a role as one of the storage tiers.  This is a subject that I plan to expound upon in future blogs.

In summary, don't believe the message that "tape is dead, just put it all on disks".  Like the economy, tape will rebound and continue to thrive as the negative hype starts to get old and we hear "wolf" one too many times. 

Posted at 11:05AM Jun 04, 2008 by Greg Secrist in Sun  |  Comments[0]

My first entry .... about this blog ...

So I decided to take the plunge and start my own Sun blog. Thanks to Mr. Neely and my other cohorts for twisting my arm enough to finally start putting my so called "insightful" thoughts out to the storage community at large. I've entitled my blog as ILM and everything else under the "SUN". My main blog subject will be my take on ILM (what it is and what it is not), and my experiences with customers and peers as I continue down this road of ILM consulting. I will also, occasionally, blog on everything else to do with stuff here at Sun Microsystems. After all, ILM is not relegated to just a storage topic and the storage component within the IT technology stack. It is a concept, way of thinking, and approach to managing and organizing data (that contains information) throughout the entire data path. This data path touches different stacks of technology through its lifecycle, thus the whole idea of managing the lifecycle of the data (information) from creation, to resting place, to recall at some point down the road. Ok, I'm already on my soapbox and this is supposed to be an introduction to my Sun blog. More to come as I find time to write on the plane, at the airport, and anywhere else as I travel from customer to customer delivering ILM and storage consulting services. Stay tuned ...

Posted at 10:53AM May 31, 2008 by Greg Secrist in Sun  |  Comments[0]