Using a new test that can simulate large-scale Fibre Channel fabrics, testing equipment vendor Spirent Communications says it has found that none of the FC switches it's tested is able to support fabrics that scale up to the theoretical maximum number of switches in a single fabric provided for in the Fibre Channel specification.
Spirent's Storage Routing Tester, to be available later this month, is a software module that runs on the company's SmartBits test system. The software, which has a list price of $40,000, is able to simulate up to 238 Fibre Channel E-ports per SmartBits port, making it the first test equipment to be able to generate SAN switch traffic in addition to that of end devices.
According to the industry's Fibre Channel specification, FC switches should be able to support up to 239 switches in a single fabric -- but none of them can actually do it, says Brian Mason, product manager for storage solutions at Spirent.
"We've found major scaleability concerns with all of the NEMs [network equipment manufacturers]," Mason says.
After the original version of this article was published, however, Spirent backtracked. The company sent Byte and Switch a statement that said, in part: "Spirent has worked with many vendors' switches but not all vendors and not all their products. As a neutral party, we cannot make a public assertion that no vendor in the industry can scale. Of the vendors our test equipment has tested, some stop at lower numbers and some numbers go beyond 200."