As companies continue to increase their storage capacity at double digit rates, while also virtualizing their data, getting that massive data out of storage and into the hands of end users requires a new generation of storage switches.
"IT environments have evolved in a silo fashion resulting in architectures that are inflexible and complex to operate," says Edgardo A. Lopez, product marketing manager for Hewlett-Packard Company's StorageWorks product line in Marlborough, Mass.
The answer, he says, is to create adaptive infrastructures, built from standard building blocks that allow the data center to operate automatically in a lights-out environment.
"The next generation data center is a dense environment of virtual computing requiring massive storage and more reliable bandwidth," says Lopez. "As a result, the data center storage network is also evolving to match those changes within the context of the adaptive infrastructure."
Faster and Cheaper
Fibre Channel (FC) has dominated the SAN market since the standard hit the market in 1997. Since then, FC has regularly increased its speed, now topping out at 8 Gbps.
"Each new generation of Host Bus Adapters (HBAs), because they are made with a new chip at a new chip size, usually results in a higher performance adapter costing less than the old one at the slower speed," says Gartner research VP Robert E. Passmore. This doesnt mean, however, that the SAN performance will increase proportionally. "Most servers dont know what to do with 1Gb, much less 2, 4, 8 or 10," he says.
So, while increasing speed is good, the biggest change in the server storage has been the rise of iSCSI as an alternative to Fibre Channel. iSCSI, a protocol that layers SCSI commands on top of TCP/IP, allows companies to use standard Ethernet switches and Network Interface Cards, rather than the more expensive FC switches and HBAs. Low hardware price, however, comes with a performance cost due to TCP/IPs high overhead.
"When the server is not doing much I/O, is not that heavily loaded, if you benchmark FC vs. iSCSI, you will get comparable application performance," says Passmore. "But if an application is using up the server and doing lots of I/O, you are going to get very poor performance out of iSCSI, while FC will sit there and hum."
Consequently, iSCSI tends to work best in smaller, lower performance SANs, while FC is still the choice for mission critical enterprise SANs.
Next Gen Storage
HP has a complete line of storage switches which it has revised over the past year to meet a variety of applications. For its BladeSystem c-Class, the company introduced a new set of embedded switches that support advanced technologies from both Brocade and Cisco.
"Both the Brocade Access Gateway Mode and Cisco N-Port Virtualizer extend the capabilities of the embedded switches with N-Port Virtualization support, thus enabling them to act as HBA aggregators rather than as traditional switches," says Lopez. "In this mode, they become I/O devices that continue to provide value through reduced management, greater scalability, lower cost through reduction of cables and SFP's, and greater interoperability option since they do not connect as an E-port to the fabric."
HP has also added several new products to its B-Series portfolio. The StorageWorks 4/32B SAN Switch is a mid-range 4Gb FC switch for small SANs or as an edge switch on a larger SAN that uses 20% less power than older models. It also released a new iSCSI blade for its high-end StorageWorks 4/256 Director and added FICON support for mainframe environments.
In its C-Series, HP introduced the MDS 9124, a 24 port, 4Gb FC fabric switch and the MDS 9222 MultiService Fabric Switch. For its C-Series Directors there is the new 9000 18/4 MultiService Module.
"This high performance module or blade turns any MDS 9200 Fabric Switch or 9500 Director into a Fibre Channel Switch, SAN Extension Gateway, iSCSI to FC bridge, or router for optimum flexibility," says Lopez.
The company also introduced the StorageWorks IP Distance Gateway to connect and replicate data between SANs using an IP connection.
"HP's focus is on delivering complete end-to-end solutions that solve customer problems," he says. Switches, directors and multi-protocol gateways are important components in this larger solution, but the real value for the customer is in a complete, reliable infrastructure solution that delivers on the promised value."
This article was first published on EnterpriseITPlanet.com.