Adaptec’s Impressive New Snap Server Line

With the Snap Server 700i series, by contrast, Adaptec has delivered a truly non-disruptive vertical and horizontal scaling approach in the form of "auto provisioning."

Last week, Network Appliance filed a lawsuit against Sun Microsystems charging that the latter had infringed on its patented intellectual property in the file system code, called ZFS, that Sun had released into the open source community a couple of years ago. Notably, the particulars of the suit were articulated first in a blog by NetApp CTO David Hitz, rather than in a formal press briefing or news release. Even more noteworthy, Sun’s response to the charges, which they say are without merit, came in a blog posted by Sun CEO Jonathan Schwartz.

Relying on the blogosphere might connote to some just how important non-traditional media has become in the general state of affairs. The trade press that picked up the story (most of them, since it has been a while since we had an interesting legal fight between storage companies) must have found it strange quoting blogs for the source of their information. Some were grimacing as they did so.

The whole affair took on the all-too-serious but nonetheless funny flavor typically associated with things like masked wrestling in Mexico, the Lucha Libre, recently popularized in movies such as the comedy Nacho Libre. Not only was the debate over the merits of the case being handled in the blogosphere, but the entire basis for the case—trying to get an injunction to prevent products from being developed based on a piece of code that is now "in the wild" of the open source world and has been for at least a year—seemed, well, idiotic.

What made the story really funny was that Schwartz used his blog not only to answer—and dismiss completely—the charges made by NetApp, but also to advertise a product based on ZFS, a NAS product called "Thumper," that was a lot cheaper than NetApp Filers at a little over a buck per GB and that offered the same baseline functionality.

Network Appliance CEO Dan Warmenhoven told me in the call announcing the lawsuit, which will play out in a federal district court in Texas (where they apparently have the skills to evaluate tech IP infringement cases, according to Warmenhoven), that NetApp would first pursue the injunction and compensatory damages for intellectual property theft against Sun. Then, they might go after any products that are built on ZFS when "they become competitive" to NetApp wares.

I suppose this was intended to have an immediate chilling effect on Sun’s Thumper sales . The reports I have received from integrator/resellers, however, is that customers are more interested in Thumper today than ever before, mostly as a result of the publicity given in the case.

This probably confirms the new adage that you can’t lock the arena doors after the Luchadores have already escaped.

Against this backdrop, it might have gone unnoticed this week that Adaptec released its strongest line of iSCSI storage targets yet, the Snap Server 700i Series. We had the opportunity to test two products in the series, the 720i and 730i, in our labs and wrote several papers describing their virtues as hosting platforms for Microsoft Exchange and Microsoft SQL Server (you can read them in their entirety on Adaptec’s Web site).

Adaptec’s Snap Server 700i Series of iSCSI storage platforms feature capabilities that can improve significantly upon Microsoft’s built-in protection functions, such as Cluster Continuous Replication (CCR) services. The 700i series, for example, delivers continuous data mirroring between 700i series platforms, application-consistent snapshots that can be stored on another Adaptec Snap Server 700i series product, and a variant of auto-provisioning functionality that enables drives to be added to a volume without disruption of array operations.

In our tests, we set up Adaptec’s continuous data mirroring, called a "mirror-plex" in the vendor’s parlance, between a 730i and a 720i system. Unlike some mirroring solutions, Adaptec’s mirror-plex does not require one system be designated as the target for the operation. Rather, the two systems can mirror each other—or work with a third target—at the same time.

This is a very useful feature in Exchange Server environments, where mailbox services may be spread across multiple physical servers in a campus setting. With Adaptec mirror-plex, each storage array associated with each physically distributed mailbox server can be used as a mirror target for its peers. Failover can then be established to provide access to the primary data required by an Exchange Server at any physical node in the mirror configuration.

Setting up a mirror-plex in our labs took less than a minute. Synchronizing a 2TB dataset over a Gigabit pipe required approximately 60 minutes. Once established, the impact of mirroring on normal write operations was barely perceptible.

That’s all good. To my way of thinking, however, where the Snap Server 700i Series really shines is in Adaptec’s homegrown Application Consistent Snapshot facility that enables multiple LUNs in the same array (or spread across several 700i series products) to be grouped together in a snapshot image. All mounted volumes used by Exchange Server or SQL Server can be included in a single snapshot, providing an application-consistent copy of the data at a particular point in time. This is a much superior approach to the snapshot techniques employed by other vendors that focus on individual LUNs rather than on the volumes that an application actually uses.

With application-consistent snapshots, Adaptec has built a powerful resiliency case for using its 700i platform to host Exchange Server data. One plus: Adaptec’s snapshot facility makes use of Microsoft’s own Virtual Disk Service and Volume Shadow Copy Service (VDS/VSS), so there is no need to buy additional shadow-copying software or to takingExchange Server offline while creating snapshots.

Finally, we tested the third leg of Adaptec’s resiliency story: failover. First, we configured a mirror between a 730i and a 720i unit. Then we disrupted operations, first, by disconnecting the 730i from the switch by unplugging its Ethernet cable (for simplicity, we used only one of four ports on each Adaptec unit to perform the test). The disruption event was detected immediately by the 720i, which picked up the new load without disrupting Exchange Server operations. (Iometer was used to generate I/O for testing purposes and no errors were reported.) We repeated this test by disconnecting power from one of the iSCSI targets and got the same results.

There is no voodoo here, and no VMware in the equipment to facilitate failover. It is just good, solid engineering by Steve Rogers’ team at Adaptec.

Performance of the system was on a par with iSCSI products costing substantially more. Rogers and company built multiple iSCSI ports into the heads of the units and decided to use Microsoft Multi-Path IO (MPIO) to provide automatic load balancing. Unfortunately, this ran afoul of some bugs in MPIO, but the fallback, assigning target ports and traffic paths by hand, worked well.

Exchange Server and SQL Server environments tend to be dynamic. The volume of e-mail and database data that companies amass has a tendency to expand over time, creating a need to scale storage platforms (and protection services) to keep pace. The storage industry has paid considerable attention to this issue, yielding solutions that range from "storage clustering" (the ability to add additional nodes of storage into a clustered group) to "thin provisioning" (using reserved but not allocated capacity to buffer allocated space).

Despite all of these new technologies, however, scaling a storage array remains a highly disruptive process. Applications must be stopped and storage systems must be powered down so that additional drives (or trays of drives) can be added or so existing drives can be replaced with newer, higher-capacity units. With the Snap Server 700i series, by contrast, Adaptec has delivered a truly non-disruptive vertical and horizontal scaling approach in the form of "auto provisioning."

Auto provisioning is a much overused phrase, generally applied to describe an automated process by which storage capacity is assigned to specific applications. Adaptec’s auto provisioning includes this functionality, but takes it to a new level. An easy-to-use EXTEND VOLUME wizard can be leveraged to add capacity from any available storage pool to any existing volume. The changes to volume size are made automatically and without disrupting application operation and we noted no performance degradation as the adjusted volumes were being resized. This is an excellent facility that we have only seen in storage virtualization techniques applied outside of arrays.

Given the price tag on the 700i Series, which is similar to Sun’s Thumper, and well below the cost of anything offered by Network Appliance, this might be the iSCSI target to beat when building storage behind Microsoft’s more demanding apps.

Let the Luchadores fight it out in the federal courts. Adaptec has a good story to tell in the areas of resiliency, performance, scalability and price. It's worth a close look.

Your views are welcome: