Time was when routine tasks like data migration and load balancing required applications or entire networks to be taken off-line, leading to collective groans from employees and untold amounts of lost productivity.
Intelligent SAN switches and specialized block virtualization software have gone a long way toward making those dreaded "the network is down" announcements a thing of the past. But enterprise managers are still contending with I/O bottlenecks as more and more virtual systems seek to push data through the same physical interconnects.
To address this problem, much of the focus is on virtual I/Os. But there's a growing movement that's calling for placing more intelligence on the network level with an approach called split-path architecture. This article from EMC's Doc D'Errico offers an inside view of how a new breed of port-level ASICs is able to open up Fibre Channel frames and perform I/O mapping and re-routing in less than 20 microseconds. By divorcing these I/O requirements from the CPU, you instantly boost resources dedicated to application processing and other higher-value functions.
EMC is supporting this approach through new backup and recovery tools, like the RecoverPoint data protection system. With a split-path design, you can host it on an out-of-band appliance using either a host agent or an in-band intelligent switch.
Another supporter is Emulex, which is using split-path to support SAN-based storage virtualization. With the company's Model 765 Intelligent Services Platform using separate control and data paths, data delivery speeds are boosted through hardware acceleration and a 20 Gbps application processing engine.
LSI Logic recently signed on to the Emulex approach, offering to carry the 765 platform on the Storage Virtualization Manager appliance, where it will be tied directly to Emulex's AV510 intelligent storage processor. The pairing brings compatibility with all major SAN fabrics, namely VMware, at 1.4 Gbps.
It's always tempting to see a new technology as the next big thing. Split-path architecture is probably best seen as one adjunct to overall network health, along with virtual I/Os, acceleration technology and everything else under the SAN.