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]