Original URL: https://www.theregister.com/2010/02/10/ibm_sonas/

SONAS offering from IBM covers much ground

Scale-Out NAS - again

By Chris Mellor

Posted in Channel, 10th February 2010 14:10 GMT

IBM has launched Scale-Out Network-Attached Storage (SONAS) from one of the far corners of its widespread storage empire - out of the (big) blue, you might say.

News came via a tweet from an Ideas International analyst, Chris Ober: not your usual IBM product announcement method. There's an IBM web page here, but there's no press release as yet. Nevertheless, it has got the industry talking.

SONAS is an Isilon-like clustered NAS system. It has separate Interface Nodes (IN) and Storage Pods (SP), clustered globally, IBM says, together across an InfiniBand network - speed unknown. IBM says this can be geographical in scope. There are separate management nodes which talk to the Interface Nodes and Storage Pods across a 1GbitE link.

Accessing servers and applications come in across an IP network and use NFS and CIFS protocols, or SCP (Secure Copy Protocol), HTTP or FTP. They are presented with a single global namespace and a first release file storage capability of up to 14.4PB, meaning billions of files.

SONAS is built using IBM's General Parallel File System (GPFS). This widens the competitive product environment to include HP, with its PolyServe and Ibrix technology, as well as Isilon, whose NAS cluster can scale to 10PB and 144 nodes.

A Storage Pod is built from two storage nodes; I'm thinking like dual storage controllers here, each of which talks to two separate disk enclosures, so we get access path and controller failover. The storage enclosures can be from 4 to 16U high and hold 27TB to 480TB of data, with either SAS or SATA drives being supported. These are aggregated into physical storage pools and then logical ones. Data is striped across all drives in a logical pool.

The capacity numbers would suggest a 4U box holds 27 1TB drives - which seems an unusual number - and a 16U box with 480 1TB drives, which seems a more sensible round number. IBM does not say whether it's using 1 or 2TB SATA drives and nor does it talk 2.5-inch or 3.5-inch formats.

IBM isn't saying, but we'll assume 3.5-inch SATA drives for capacity and SAS drives for speed. Big Blue says automated ILM (Information Lifecycle Management) is coming and that will include transparent migration at a file level between disk tiers and to external tape storage, all of which will be transparent to accessing apps, servers and users. The ILM will involve what IBM calls a high-performance scan engine, which also enables a fast search ability the product comes with.

In version one, there can be up to 30 Interface Nodes and 30 Storage Pods in any combination, as you vary IN counts for interface performance and SP counts for capacity needs. All nodes are said to get involved with searches, to provide fast search response in the PB-plus data space.

IBM says that SONAS comes with thin provisioning and both synchronous and asynchronous replication. It has automatic load-balancing and is self-healing, working around failed components.

The overall pitch is that existing clustered NAS can't work with PB-class storage requirements. This is because the overheads of managing the scalability required are too great and you have to fall back on to separate NAS products. Isilon might beg to differ.

IBM used to have, and probably still has, a Scale-out File Services (SOFS) offering which was also based on GPFS. SONAS appears to be SOFS mark II.

IBM says the number of Interface Nodes and Storage Pods can be scaled up or down in real time. The system supports the presence of INs and SPs in remote offices, alongside a disaster recovery site and a data centre. SONAS can be used to store objects, according to an IBM SONAS brochure, although further details about that aspect of it are not supplied.

SONAS is said to be suitable for cloud storage deployment - take that Atmos - and enables enterprises to, IBM would say, manage better, scale better, become smarter, and operate better in a world where the majority of data to be stored will be in file or object format.

Now, let's add some confusion to the mix. Remember the Smart Business Storage Cloud?

In October last year we wrote:

[The] Smart Business Storage Cloud is a private cloud offering, using low-cost components in a scale-out clustered model. The components include XIV storage arrays and BladeCenter servers, plus IBM's General Parallel File System (GPFS).

There is support for multiple petabytes of capacity, billions of files in a single global namespace and scale-out performance previously limited, Big Blue asserts, to the largest high-performance computing (HPC) systems.

It seems to us here in El Reg Towers that the Smart Business Storage Cloud overlaps considerably with SONAS. Hopefully IBM will clarify the confusion.

It's interesting by the way, that this news comes the day after it's revealed Dell is looking to buy the remains of clustered NAS supplier Exanet.

There is no SONAS pricing information, no availability information and no canned configurations up front from IBM, so talk to your local IBM rep and ask him or her to give you the SONAS story. There's also an IBM brochure (pdf) which we downloaded yesterday, but are having persistent download problems with today. Good luck. ®