Data management application programming interface handling mount on multiple nodes in a parallel file system

A computer software product for use in a cluster of computing nodes having shared access to one or file systems in data storage, accessed using parallel file system software, the product comprising a computer-readable medium in which program instructions are stored, which instructions, when read by the computing nodes, cause a session of a data management application to be initiated on a first one of the nodes, and in response to a request submitted to the parallel file system software at a second one of the nodes to mount one of the file systems in the data storage on the second node, cause the second node to send a mount event message to the first node, for processing by the data management application on the first node,

• wherein the instructions cause the nodes to mount first and second instances of the one of the file systems on the first and second nodes, respectively, responsive to the mount event message, and
• wherein responsive to a further request at the second node to unmount the second instance of the one of the file systems at the second node, the instructions cause a preunmount event message to be sent to the first node, and cause the first node to respond to the preunmount event message so as to permit unmounting of the second file system instance without unmounting the first file system instance.