Figure 55 Direct Library Access

Device sharing in clusters

Clustering, which is often used in combination with the SAN concept, is based on sharing network resources (for example network names, disks, and tapes devices) between nodes.

Cluster-aware applications can at any time run on any node in a cluster (they run on virtual hosts). To perform a local backup of such an application, you need to configure devices with virtual hostnames instead of real node names. Configure as many devices for each physical device as you need, using the Lock Name device locking mechanism. For details, see “Device locking” on page 177.

Static drives

Static drives are devices that are configured on a real node in a cluster. They can be used to back up data from systems with disks that are not shared. However, they are not useful for backing up cluster-aware applications, because such application can run on any node in the cluster.

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Media management and devices