But Clark does acknowledge the inordinate consumption of domain IDs is an issue, and one that McData is working on. Clark says that work revolves around how QLogic does its implementations and on how McData and QLogic work together to satisfy the appetite of the blade switches for domain IDs.

Clark goes on to explain that major switch vendors have an "open mode" to minimize interoperability problems in heterogeneous environments and a proprietary mode for use with homogeneous systems. In open mode, the switches sacrifice their proprietary, value-added capabilities. For example, he says, when Brocade switches are in open mode, they sacrifice some zoning capabilities.

How to preclude problems

Bob Shinn, a former manager of storage and now director of service delivery at State Street Global Advisors in Boston, has a suggestion for would-be multivendor SAN users: Hire a third-party consultant firm to help with implementations.

"Don't overspend on this, but you should absolutely hire someone that you know you can trust," Shinn says. "You need someone you can work with that has experience in this area and [in] maturing a storage environment. That way, you can skip some of the growth pain."