HP 3PAR flattens the SAN
Virtualised I/O for BladeSystem servers
HP announced a direct Fibre Channel connection  at its Discover event in Las Vegas on Monday, between a 3PAR array and BladeSystem servers using Virtual Connect. This simplifies the storage area network (SAN) fabric enormously and saves a ton of cash.
A BladeSystem is up to 16 servers in an enclosure that plug into a high-speed backplane. Ethernet, Fibre Channel and iSCSI switches plug into the back and connect the blades to what is at the end of those links. The Fibre Channel fabric is set up in the traditional way with switches, directors, and so forth.
More importantly, a Virtual Connect FlexFabric box can connect to the backplane and share whatever is plugged into it. In this case a 3PAR array connects to it using one or two Fibre Channel cables - 8Gbit/s ones we think - and its storage capacity is accessible by all the servers in the BladeSystem. This is a fine example of HP's converged infrastructure.
The two cables are for redundancy. A maximum of four Fibre Channel cables can come out of the Virtual Connect box and link to two, three or four arrays.
What's happened is basically a cable connection and Virtual Connect firmware upgrade. Other, third-party, Fibre Channel arrays could also plug into the Virtual Connect box, according to Jim Ganthier, VP marketing and operations in HP's Industry Standard Servers and Software (ISSS) group. This means no vendor lock-in.
3PAR VirtualConnect flat SAN does not negate the classic heterogeneous SANs we all know - it is for the 3PAR-Bladesystem link in HP's converged infrastructure, according to David Scott, HP's StorageWorks head.
Ganthier says that network latency is cut up to 60 per cent in a flat SAN, by replacing a multi-layer Fibre Channel fabric with simple cable connections. That would be, for a single frame, moving from 7,100 nanoseconds to 2,840ns, according to figures I have seen.
HP slides talked about a BladeSystem supporting 25,000 virtual machines (VMs). But that's an approximation, and Ganthier said a 3PAR array connected in this flat SAN way couldn't support anything like 25,000 VMs. He didn't have a precise figure.
He couldn't comment about speeding up the network link between the 3PAR array and the Virtual Connect box by, for example, moving to an InfiniBand link and so cutting network latency further.
Craig Nunes, an HP marketing veep for the ISSS group, told us to stay tuned when asked about an all-flash 3PAR array, which would cut latency even more. We might therefore think about a future Converged Infrastructure offering of a BladeSystem with an all-flash 3PAR array linked by InfiniBand to the Virtual Connect box; shades of Xsigo .
We could also envisage HP's StoreOnce deduplicating disk-to-disk backup system connected to BladeSystem servers by Virtual Connect. ®