IBM released a new Data Ontap version last Friday along with some other minor releases but more about those later. Data Ontap 8 7mode was the first release of a new 64-bit architecture that will allow N series customers to take advantage of larger aggregates.
A little history. Back about 8 years ago, Netapp purchased a company named Spinnaker for the use of their 64 bit code, global name space and some other odds and ends. For the most part, Netapp has been re-branding this code as their GX platform allowing customers who want the feature set to purchase it aside from their Data Ontap base. GX was not a heavy seller as it was complicated to install and much more pricey than the other brand and Netapp decided to co-mingle the two code streams into one. At first glance this sounds like a good idea. The Data Ontap code definitely had some limitations (small aggregates sizes, limited growth and no global name space) but the merging of the two streams was harder than Netapp imagined. This was shown by Netapp promising a release of the new merged code for over years and finally a release was available for testing.
There were many bugs (as RC code can be) but Netapp worked through the majority of them to produce a stepping stone release of the merged code called 7 mode. The developers used bits and pieces of the GX code to get the 64-bit architecture allowing customers to build larger aggregates, up to 100TB in size. This was really important as the release of the 2 TB Sata drives were coming and the limitation of 16TB in an aggregate would of killed any performance on the system. With only 8 2TB drives in the aggregate, the maximum IOPs throughput would be limited to about 400 IOPS per 16TB of drive space, not a good ratio at all. Therefor having a larger aggregate size allows them to put up to 50 2TB drives achieving a more respectable 2500 IOPS per aggregate.
Now that we have the 7 mode available, there are some upsides and some downsides. First, as stated above, the aggregate sizes have increased tremendously. Allowing for more data disks in the aggregate increases the amount of IOPs the filer can pool. On the downside of this news, we see that you can not simply flip a switch and increase an aggregate created in the old 32-bit code to a new 64-bit aggregate. Customers will have to create a new aggregate after upgrading to the 7-mode version of Data Ontap 8 and then migrate with some restore method (think DR restore from backup) on to the new space. You can not mirror the two as SnapMirror can only mirror between like for like aggregates (32-bit to 32-bit and 64-bit to 64-bit). No big deal if you are new customer or if the filer is a new addition to the filer farm, but for those existing customers I believe this will be a lot tougher. If you do not have the drive space to create a new 100TB or less aggregate, you will have to either wait to buy more disks or do a manual backup (not snapshot), destroy the existing aggregate, and build a new aggregate on the 64-bit code, then restore. This is and the fact this is the first release of the new code family, will be why customers will not adopt the new code very quickly.
There are also some other gotchas like no support for Performance Accelerator Cards (PAMII), no real interoperability between the two code bases and more. When I was an administrator, I hated having to read the release notes for the 'fine print gotchas' but in this case I encourage everyone to read the notes thoroughly and perhaps engaging your local IBM Storage engineer to help you access if you are a good candidate to upgrade or not.
The fact this is a stepping stone to the full code line does help customers that need to move to the 64-bit architecture today without slowing down Netapp's development team. They are working on the next release of Data Ontap 8 called cluster mode. This will be the code that allows customers to cluster more than one pair of systems under one global name space. I suspect this will be a great addition to the Data Ontap code line and will give Netapp more traction in the larger enterprise business.
There were also some firmware releases for the EXN3000 shelf on Friday as well. For more information on what was released, visit www.ibm.com support page