Federated storage offers scalability, availability and ease of management for organisations that require large amounts of flexible storage to support growing IT infrastructures. Many of these functions are being built into clustered NAS and SAN products, but will we see federated storage arise as a distinct product category?
In this interview, SearchStorage.co.UK Bureau Chief Antony Adshead speaks with Chris Evans, independent consultant with Langton Blue, about the definition of federated storage, its use cases and benefits, federated storage products, and the technology’s prospects for the future.
You can read the transcript below or listen to the podcast on federated storage.
SearchStorage.co.UK: What is federated storage?
Evans: There is a definition that most people tend to use. [They define] federated storage as the transparent, dynamic and non-disruptive distribution of storage resources across self-governing, discrete peer storage systems.
Now that sounds like a mouthful but effectively what it’s saying is you’ve got a number of separate storage arrays which together are working towards producing a storage infrastructure against which you can write data.
That’s very different [from] the way things are done today, where perhaps a single array might be linked to another but there’s a certain overall control involved. [Federated storage allows] distribution of the control and the locking mechanisms to be given to each of those arrays so that any of those devices can take part, and it means you can add in and you can take out devices over time.
We can pretty much split it into two areas, so if you look at the SAN environment and the NAS environment we have federated storage devices in each of those. … In something like NAS, that would be a scale-out device that allows you to deploy nodes perhaps geographically or something similar.
In the SAN environment, those would be storage arrays where you can write data to each of the SAN arrays and have that written to the same LUN, potentially at the same time, or have it appear to be written at the same time.
SearchStorage.co.UK: What type of organisation and data storage use cases is federated storage suited to?
Evans: We’ve touched on what it would do, and one of the things we talked about a lot is scale and the availability side of things, so clearly some organisations are looking to manage a lot of data, some want high availability, some want to distribute their data. Federated storage would allow you to meet those sorts of goals.
So, for instance, if you were a large organisation [that] needed to deploy multiple petabytes of storage but you didn’t want to have a single device that you were reliant on or you needed to spread it around, this would be one way of doing it.
For instance, in the SAN environment you may be an organisation that needs to have a high-availability setup, and if you had a federated storage SAN environment, that would allow to write data in multiple locations, and there’s a good example of a technology that fits well with that, which is server virtualisation. … The VMware cluster could be spread across a number of sites and could write to that storage at the same time.
SearchStorage.co.UK: What are the benefits of federated storage?
Evans: If I was looking to put in a federated storage solution, I’d say it would give me a number of different benefits. The sort of things I’d be looking to see would be the scalability, the availability and functions such as being able to move data in and out of that environment seamlessly without having to take outages on it, plus the ability to add to that cluster or environment and put in more technology. For instance, [if] I need to … put in another node, what I don’t want to do is take that node down, so it’s given me scalability, it’s given me availability, it’s given me better management so I don’t have to take as many outages and so on.
SearchStorage.co.UK: What types of products are organisations using to build federated storage infrastructures?
Evans: You can get federated storage products in the SAN and the NAS market. One of the ones we’ve seen in the SAN environment, which is a good example, comes from EMC, and that’s their VPlex product. This was a piece of technology that came from a company called [YottaYotta] that EMC bought a few years ago. EMC has taken that technology, changed it around and used it to create VPlex. They put that above VMAX and allow that to integrate into their VMware environments, and that gives a lot more flexibility in the way that data can be moved around.
We’ve also seen products from EqualLogic, [which] has always had products with federated features so you could always add another cluster and spread data around for load balancing and performance reasons, and obviously we’ve seen a range of NAS products. Recently we [saw] Isilon being purchased by EMC, and they offer a similar functionality in that you can create a cluster and you can add data to that and create a federated environment.
SearchStorage.co.UK: Are we going to see federated storage increase in prominence, and, if so, why?
Evans: Clearly, you could look at this and say that this has been driven by the vendors and they’re looking for another angle to sell you something different, and I think this sort of product has always existed in some form or other.
I would expect [federated storage] to become more prominent because as people scale up to having larger and larger environments, have less and less time in which they can take these environments down, and want to integrate them with more virtualised technologies such as VMware, Hyper-V and so on, then federated storage is going to become more of a requirement because it helps to deliver to those infrastructures. It certainly gives you those features of scalability, performance and management.
I think what we’ll see in the next few years is rather than it becoming something that’s sold as a big, brand-new feature, it will become the norm within the products as they move forward, and we should expect to see federated storage … being a standard feature of large-scale enterprise storage systems.
This was first published in April 2011