Fewer cables in your future
As data centers become increasingly packed with servers and equipment, facilities managers can take comfort in knowing that at least some simplification is coming. Cisco Systems is leading an effort to develop what it calls Unified I/O.
The idea behind Cisco's input/output system is to reduce the number of communications cables emerging from servers ' a number that seems to keep increasing. Steve Picot, Cisco's federal sales manager, said a server can have as many as six different network card connections, each requiring a cable. One might be for the storage network, one for redundancy, one for out-of-band management, one for virtualized machines, and so on. For example, Sun Microsystems' Sparc Enterprise T5120, for instance, comes with 10 Gigabit Ethernet cards.
Also, virtualization seems to be resulting in more network connections per box. James Rankin, a technologist at CDW Government, recommended having at least four network cards for virtual environments, including one for the regular network connection and one for out-of-band maintenance. The virtual guests would be a primary and backup.
Unified I/O can consolidate all the network connections into a single 10 Gigabit Ethernet connection large enough to accommodate all traffic, which can be separated into channels, each with its own throughput and quality of service.
Vendors such as 3Com are preparing network cards that keep track of the multiple protocols, Picot said. Cisco's own Nexus 7000 line of switches will support Unified I/O.
A similar effort to reduce cables, Picot said, is Fibre Channel over Ethernet. This is a standard that eliminates the need for separate cables by letting Fibre Channel connections in storage area networks run via Ethernet cable.
A more immediate reduction in cabling might involve migration to blade servers.
Ron Bryson, an American Systems program manager, was recently involved in the build-out of a government data center that switched in the design phase from regular rack servers to blade servers. This change reduced the number of cabinets needed from 200 to 86 and the cabling requirements from 100 lengths of 48-strand fiber to 30 lengths.
Lim Goh, chief technology officer at SGI, said he sees data centers moving toward blade servers to take advantage of the simplification they offer.
Instead of running cables from each server to the access layer switch, he suggested using a rack and set of identical blade servers with an integrated backplane.
'Instead of running cables to external switches, put those switches in the rack,' Goh said. 'This is where the industry is going.'