Clustered storage technology

This week our Special Focus takes a look at products that promise to combine disparate file systems into a single package with a single namespace. These clustered or SAN file systems have several advantages over distributed file systems according to our author (dconnor@nww.com):

* By clustering systems and sharing applications and data, tasks can be performed much faster than they could on individual machines because data doesn’t need to be copied or replicated from one file system to another.

* Clustering provides more space for files and file systems.

* Management is easier because only one file system is being managed not a file system for each storage device or host computer.

* Failover is available because one server in the cluster can take over the responsibilities of another if it fails.

* Users have concurrent access to all the files located on the storage devices on their network.

In a cluster, a group of independent nodes or host computers work together as a single system. They may share a common storage array or SAN and have a common file system that has a single namespace. A traditional example is HP’s Tru64 cluster file system used in TruCluster systems.

More recent implementations are from Red Hat, Oracle, Cluster File Systems and start-ups Panasas and Spinnaker Networks, among others. Red Hat, who acquired Sistina last year, released its clustered Global File System into the open source; Network Appliance, who acquired Spinnaker Networks, is using its SpinCluster software to bolster its grid strategy, which clusters network-attached and SAN storage. Oracle uses its Cluster File System on the company’s Real Application Clusters (Oracle 9i RAC); Cluster File Systems uses its Lustre File System to build high-performance compute clusters.

For more on this story see: https://www.nwfusion.com/news/2004/0322specialfocus.html