Red Hat RH00387, Lisenssi

Red Hat's Resilient Storage add-on enables a shared storage or clustered file system to access the same storage device over a network. By providing consistent storage across a cluster of servers, Red Hat's Resilient Storage add-on creates a pool of data, that is available to each server in the group, but which also is protected, if any one server fails. The Resilient Storage add-on provides numerous file system capabilities for improving resiliency to system failure. This add-on features the Global rile System 2 (GFS2) for supporting concurrent access; a Portable Operating System Interface for UNIX (POSIX)-compliant file system across 16 nodes; and Clustered Samba (a clustered common Internet file system), or CIFS (for concurrent files shares in a Microsoft Windows environment). When using the Resilient Storage add-on, a single version of all files in a cluster is visible to all nodes within that cluster. Each server in a cluster has direct access to a shared block device over a local storage area network (SAN). Data and cache consistency is ensured using a cluster-wide locking mechanism called distributed lock manager (DLM) to arbitrate access to the storage. Each member of the cluster thus has direct access to the same storage device, and all cluster nodes access the same set of files.