Patent ID: 7689759
Filing Date: 2010-03-30
Classification: G06F

Abstract:
1. A method for providing continuous access to shared tape drives from multiple virtual tape server (VTS) nodes, said method comprising: connecting a first VTS node and a second VTS node to a plurality of tape drives via a plurality of switches, wherein said first VTS node includes an active database and said second VTS node includes a standby database; redirecting all requests received by said standby database to said active database; in response to a volume mount request on a physical volume, placing a lock on a tape drive table by one of said two VTS nodes handling said volume mount request to preventing any access to said tape drive table from one of said two VTS nodes not handling said volume mount request; selecting an available physical tape drive to mount said physical volume and marking an entry within said tape drive table to claim ownership of said physical tape drive by said VTS node handling said volume mount request; sending drive reservation request to said physical tape drive to prevent any access to said physical tape drive, and releasing said lock on said tape drive table by said VTS node handling said volume mount request; and performing said volume mount request by said VTS node handling said volume mount request.