ORLANDO, Fla. -- As the debate over where advanced storage services will reside rages on, EMC Corp. previewed its...
Storage Router for the first time at Storage Networking World this week.
The Hopkinton, Mass., storage company demonstrated a dynamic volume migration application running on the product, which under the covers includes a Brocade Communications Systems Inc. 7420 intelligent switch and a separate control path processor running on a server. A 200 MB movie clip, residing on an HP EVA 5000, was migrated to an EMC CX 500 while the application continued to run. The operation took approximately one minute. They did the same demo a second time using Cisco's Systems Inc.'s MDS 9216 intelligent switch with the same results.
EMC claims that when the router ships in the first half of 2005, it will support Hitachi Data Systems, Hewlett-Packard Co. and IBM arrays. It is also porting the software to Cisco's MDS 9216 and McData Corp.'s intelligent switch.
Using these intelligent switches, which have port-level processing, the copying and I/O redirection occurs at the network layer instead of the traditional host or array-based approach. The control path processor handles all the meta data functions, such as the mapping and configuration management between devices.IOU IOPS?
Although EMC didn't have any benchmark data, it claims the router will be comparable to other intelligent switches that today enable 30,000 to 40,000 I/Os per second (IOPS) per port. "With 10 to 16 processors in a blade, we will be able to scale to multiple millions of IOPS from a single point," said an EMC spokesman.
EMC's SANCopy software offers similar migration capabilities today but has to stop the application while the copy function takes place. "Customers running mission critical apps cannot afford to take these offline to move data around," an EMC spokesman said.
Other applications EMC is targeting for this product include data placement in support of information lifecycle management processes, performance optimization, dynamic reconfiguration, lease rollover and technology refresh operations.
EMC is writing these applications to support FAIS (Fabric Aware Interface Standard), a standard being developed by the ANSI/INCITS T11.5 task group. FAIS is a multi-vendor initiative, chaired by EMC, which aims to standardize the interface between storage applications and network devices.
Richard Mitchell, president of the Institute for Software Advancement and an independent trainer for storage networking exams, said he believes that network-based storage services will eventually prevail. "The array-based virtualization model locks you in to those vendors. It makes more sense to handle these services in the network as the network is the traffic cop," he said. If the array model was the correct approach, "EMC would surely do it that way," as it owns the high-end and the midrange markets, he added. That said, Mitchell stressed that the Storage Router is handling "very sophisticated stuff" and questioned how stable it will be in its first year.Once an EMC buyer, always an EMC buyer?
Eli Shapiro, CEO of StoreAge Technologies Inc., a company that has been selling a similar product to the Storage Router for the past two years, questioned whether EMC will be "truly hardware agnostic," and argued that it will come down to users who will always buy from EMC versus those that are building heterogeneous environments. For the latter, a hardware independent company is the answer, he said.
Maranti Networks Inc.'s CoreStor intelligent switch is another competitor to EMC's router. It is architected to provide the I/O redirection and meta data management in a single processor. EMC spokespeople argued that this architecture burdens the processor with management functions when its primary job is to handle I/O.Au contraire
"You want these functions in a single processor for scalability," countered a Maranti spokesman. He said EMC's offering is limited to the distance of a single data center because of the connectivity needed between its control path processor and the switch.
It would seem that even among the network-based approaches to virtualization, there's no one way to skin the cat.
Ross Pincus, manager of midrange operations at SunGard Availability Services and a major EMC user, said that it will be "a long time" before he trusts the network model for providing storage services. SunGard provides disaster recovery services and runs hundreds of different operations for its customers. "We keep each SAN for each customer physically isolated, as we can't risk one seeing another's data," he said. Pincus is looking at the HDS TagmaStore for virtualization.