In what was something of a storage blitz on Tuesday, Hewlett-Packard announced new low-end JBOD ("just a bunch of disks") storage units, and a "NAS head" device (a filer independent of the storage attached). The company also launched SANlink, a virtualisation product which starts to deliver on the idea of allowing users to pool all their storage into one virtual device. SANlink, developed from products HP acquired last year with StorageApps, is a specialised virtualisation appliance, a rackmounted system including two servers and two Brocade Fibre Channel switches. It starts at 325,154 Euros. "Virtualisation is not new," said Tony Jones, NAS and SAN product manager for HP Europe. "It comes from the mainframe world and is now being applied on distributed open systems. In three words, it means 'One logical unit.'" At present, storage is about 40 percent utilised, so pooling it into one unit could make for greater efficiency. The product is the first step towards virtualisation under the control of HP's OpenView management software. HP claims it can already map and manage its own and third party storage systems with OpenView now. SANlink has the ability to virtualise third party storagenow -- although the list of third party products supported was not available. However, SANlink still uses its own management software, SANmaster, and won't start to come under the OpenView umbrella for a couple of months. "The first level of integration with OpenView will be available in one to two months, and will cover discovery, management, mapping and device management," said Jones. Virtualisation is currently a hot button in the storage world, with every vendor claiming to have it, or have more of it than every other. Users will compare HP's announcement particularly closely against Compaq's virtualisation strategy as, if the merger goes through, only one of these product strategies will ultimately continue. Compaq, IBM, EMC and others have been talking about virtualisation for some time, and it is hard to sort out who is ahead - especially as Compaq declined to comment on HP's announcement while its acquisition by HP is pending. HP's Jones was anxious to smooth over the competition between the two, without ceding laurels to Compaq: "Most storage vendors have similar aims: networking of storage," he said. "In that respect, its not that different for Compaq and HP." EMC's existing products are more than a match for HP's new launches, said Nigel Ghent, EMC's marketing director for the UK and Ireland. EMC is making its own moves towards virtualisation, he said. HP is majoring on network-based virtualisation, said Jones, where a specialised device handles the task, rather than host-based virtualisation. Device-based virtualisation can still provide benefits, he said. Some commentators have warned that so-called "in-band" virtualisation devices like SANlink, which sit between the hosts and the storage, will introduce a bottleneck to the system. In-band devices are the only ones that are practical now said Jones. "Out-of-band" devices, that let the host address memory directly, are available, but only from smaller players like Raidtec. "Major vendors don't offer out-of-band virtualisation yet," said Jones. "In fact, non-one but HP offers in-band virtualisation." HP bought StorageApps in 2001 for $350 million. The company's proprietary operating system, SAN.OS runs in the SANlink appliance.