SMBs often examine different cost-effective solutions for all of their data storage aspects, including choosing...
between a Fibre Channel switch or an iSCSI switch. So, which is the better deal for an SMB: an 8-port Fibre Channel (FC) switch for $4,000 or a 24-port iSCSI switch from the same vendor for about the same cost? That was the question faced by St. Cloud Orthopedics Specialist, St. Cloud, Minn.
"In terms of port count, the Fibre Channel switch was three times the cost, but that's not the whole story," said Roger Lund, systems information specialist at St. Cloud Orthopedics Specialist. Whether or not the Fibre Channel switch is a good deal depends on a number of factors ranging from your reasons for opting for FC in the first place to your estimates of storage area network (SAN) traffic.
Since the Fibre Channel switch in question was modular, "we didn't have to buy all the FC ports at once. We bought just one shelf of ports," said Lund. In fact, when the organization factored in the cost of all the other components in the SAN equation, the difference came to a few hundred dollars.
Fibre Channel switch considerations
The Fibre Channel switch may be one of the most costly components in a FC SAN strategy, but the cost of the switch shouldn't be the only consideration. There are other aspects of switches to consider, such as flexibility, modularity, speed and ease-of-use.
Traditionally, the Fibre Channel SAN was something targeted almost exclusively to the enterprise. It was considered too costly and complex for SMBs. If the SMBs needed networked storage, they could use network-attached storage (NAS) or iSCSI SAN, which cost less and was simpler to deploy and maintain..
More recently, the Fibre Channel industry began pushing to attract SMBs organizations. "Vendors certainly have lowered their Fibre Channel prices," said Mike Karp, storage industry analyst at Westborough, Mass.-based Enterprise Management Associates. They also have taken steps to simplify use of FC through GUIs and wizards. The upshot: More SMBs indeed are adopting Fibre Channel.
Fibre Channel switch vendors
The main Fibre Channel switch vendors are Brocade, Cisco Systems Inc. and QLogic Corp. Increasingly, the switches are packaged into blade systems offered by storage vendors. In addition to switches, Fibre Channel SAN users have to buy host bus adapters (HBAs), usually from Emulex or QLogic. For SMBs, "the simplest approach is to purchase an integrated FC SAN package from a major vendor," said Greg Schulz, senior analyst at StorageIO Group, Stillwater, Minn.
Saladino's Inc., a food service distributor based in Fresno, Calif., did just that. It opted for a Fibre Channel SAN from Hewlett Packard Co. built around Hewlett-Packard (HP) Co. EVA storage (18 TB), and two 4 Gbps Brocade FC switches built into the HP Blade Center. It got 4 Gbps performance (although the EVA can handle 8 Gbps), redundant power, and redundant networking for $100,000, which the company considered a bargain. Mastering Fibre Channel did not prove a problem. "HP shipped it all configured and the VAR got it up and running," said Craig Urrizola, CIO at Saladino's.
"Fibre Channel is appropriate for midsized organizations, especially those with performance-intensive needs," said Schulz. All of the major FC vendors offer entry-level products to attract midsized organizations, although it is never going to be like the IP-iSCSI world with free initiators and $300 switches. FC switches start a little above $1,000.
Slumberland Inc., Little Canada, Minn, is a classic retailer and midsize business. And it found Fibre Channel to be a business necessity. The retailer operates more than 100 stores and has 2,000 employees. "Our applications make big demands. We push a lot of transactions through. That's why we went with FC," said Seth Mitchell, infrastructure team manager at Slumberland.
Slumberland uses a Compellent SAN and set up a core-edge fabric based on a pair of 4 Gbps, 34-port FC modular switches from Cisco at the core and QLogic switches at the edge. It might have been simpler if they put in a large director-class switch instead, but "we just couldn't afford a director," said Mitchell. Even the modular Cisco switches would have been too expensive, except Cisco added a lower cost line.
Director-class switches are large, full featured switches, usually providing upwards of 128 ports. Beyond big port counts, director-class switches connect disparate SANs, use zoning to isolate data and devices within a fabric, and can manage quality of service (QoS) for different applications. They typically include inter-switch linking (ISLs) to connect and aggregate different SANs.
Most midsized organizations deploy modular switches that, typically, provide eight to 32 ports. (Brocade offers a 40-port switch.) Since they are modular, organizations can expand the port count by adding sets of ports to the chassis, usually in 8-port increments, or by connecting additional chassis. Some switches offer fixed port counts. Semi-modular switches provide slots for additional ports, but they have to be activated for a fee before being put to use.
"If the organization expects to grow or wants flexibility, it wants modular or semi-modular switches," said Schulz. An organization might grow to director scale but until it got to that point, it would have paid a lot of money for ports it wasn't using.
About this author: Alan Radding is a frequent contributor to SearchSMBStorage.com.