Network Computing is part of the Informa Tech Division of Informa PLC

This site is operated by a business or businesses owned by Informa PLC and all copyright resides with them. Informa PLC's registered office is 5 Howick Place, London SW1P 1WG. Registered in England and Wales. Number 8860726.

Clusters & Grids & Clouds! Oh My!

11:15 -- Continuing my rant on how vendors torture the English language with our very own technical jargon, today I'll examine how vendors try to apply the buzzword of the day to their product and/or service. Since "cloud" is the buzzword of February 2009, having just beat out last month's winner "green," which of course replaced "change" after the election, I'll look at how we, as reasonable storage geeks, can come up with a definition of cloud storage that serves us as users rather than the guy who wants to sell something.

In fact let's agree on a whole taxonomy to describe multi-node storage systems.

The most basic item in our taxonomy is a cluster. A storage cluster is two or more devices (computers, controllers, NAS appliances, whatever you want to call them) that work together to provide access to a common pool of storage. Clusters can be active/active, where both nodes process data all the time, or active/passive with primary nodes that process requests under normal conditions and standby nodes that only deal with requests when the primary fails.

Everything from a pair of Windows servers running MSCS or EMC Clariion or NetApp FAS with dual controllers fits the simple case of cluster. NetApp GX, Isilon, and other larger sets of systems fit here too.

Storage grids expand on the cluster concept by allowing a large or very large number of nodes to form a grid. For the sake of simplicity I draw the line at 10 nodes, in part because that's where tightly coupled clusters like the aforementioned GX and its brethren start to break down.

  • 1