The 6920 actually began shipping last year. Until now however Sun has not officially supported the device when it is used to pool or aggregate and virtualize the capacity of other arrays attached to it.
But from today Sun will support the 6920 when attached to any of its other disk arrays, or to EMC’s Clariion CX700 and CX400, and Hewlett-Packard’s EVA arrays.
This moves makes the 6920 look very similar to Hitachi’s Lighting Tagmastore, another disk array that can aggregate or pool the capacity of third party arrays attached to it. In both cases, part of the sales pitch is that the process can be used to build a tiered storage system in which data can be moved around easily.
Sun said yesterday that it will add other devices, such as IBM’s Engenio-made midrange arrays to the support list opportunistically, or when customers ask for them.
The move will not have an enormous impact on the market, as Sun does not enjoy a major slice of the external disk array market. Sun will not say how many 6920s it has sold, other than it has broken into three-digit numbers and that sales are ramping very well.
But it does add weight to the virtualization movement, in which one manufacturer’s device effectively lobotomizes another supplier’s disk arrays and turns them into dumb commodity devices, by virtualizing their disk capacity.
The other large supplier third party virtualization systems are IBM’s SVC appliance, Hitachi’s Tagmastore, and Network Appliance’s V-Series Gateways. EMC has promised to ship this quarter smart-switch based virtualization software, provisionally called Storage Router.
There is a risk that the maker of the hardware that has been turned into a near zombie slave will withdraw support, but it appears to be diminishing. Sun’s senior director Doug Wood said: EMC is probably the toughest of the bunch for this issue, but at the end of the day even they have to do what their customers want them to.
Mr Wood said that some Sun customers have already attached EMC arrays to 6920s. For its part, EMC last month told ComputerWire officially that it would not stop supporting its hardware in such a situation, although with the caveat that major responsibility for support be with the supplier of the virtualizing system.
So far data migration has been the most popular application of the 6920’s third party capability, although peer to peer cross vendor replication has also been popular, Mr Wood said.
The update to the 6920’s Unity operating code is version 3.0, which adds asynchronous and synchronous replication over Fibre Channel, and Ethernet. We needed this, and now we have it, Mr Wood said. The new code also introduces a local mirroring capability which can create four copies of data, with or without dependencies.
Snapshots taken by the 6920 can now be rolled back, and can be moved around within any virtualized capacity, and stored in an elastic virtual volume whose size can be altered at will.
