This article can also be found in the Premium Editorial Download "Storage magazine: Snaphot technology tutorial."
Download it now to read this article plus other related content.
Internal storage cloud options
If the internal storage cloud seems familiar, it is. "The storage grid has morphed into the private storage cloud," consultant Schindler said. Before the storage grid, utility computing packaged computing and storage resources as a metered service. Both concepts are similar, although the technology and architecture is different. "They were all about storage nirvana: accessing the data you want, where and when you want it, and at the cost you want," Schindler added, and without regard for what the actual storage device was or where it resided on the network.
The internal storage cloud is also similar to a network-attached storage (NAS) cluster, but with some caveats. "I'm not sure clustered NAS will scale to true storage cloud size," CommVault's Prahlad said. Although an internal storage cloud can start small, companies will want it to scale out by adding more devices.
When it comes to internal storage cloud products, the current choices are pretty thin or remarkably wide, depending on how you define the internal storage cloud. For actual products, EMC Corp. offers Atmos, which it describes as an offering for information storage and distribution. With Atmos, EMC stores and replicates a company's data through its global network depending on the service level you want. It uses business policies, policy-driven
automation and metadata to manage a company's data in this vast storage cloud, and promises operational efficiency, reduced management complexity and cost savings.
AT&T is EMC's showcase customer for Atmos as a private storage cloud. But AT&T isn't really using it as a private cloud. Instead, it will offer services involving storage through Atmos to its own customers, which is more like a public cloud reseller.
Contrary to popular assumptions, there are no giant EMC storage arrays behind Atmos. "That would be way too expensive," Nirvanix's Foskett said. Instead, Atmos' scalable capacity is delivered as JBOD. With Atmos, you get what amounts to a box in your data center with an API and a NAS interface. Or you can use a chunk of the public Atmos storage cloud as a private cloud.
ParaScale offers software specifically for creating and managing an internal storage cloud. Unlike cloud service providers, it sells only the tools that let companies build their own storage clouds. Its software runs on standard x86-based Linux servers and aggregates the direct-attached disks on multiple servers into petabyte-scale file storage in a single namespace.
Beyond Atmos and ParaScale, commercial internal storage cloud products are pretty scarce. "After those, anyone that talks about private cloud isn't really a cloud," Foskett said. Rather, they probably offer storage products that incorporate virtualization at some level, which they're presenting as a cloud. "Often, they're offering their usual product and just sticking the 'cloud' term on it," he added. Similarly, almost any NAS cluster can be presented to look like an internal storage cloud.
This was first published in October 2009