US 11,755,426 B2
Automatic recovery of locking filesystem shared between virtual tape library nodes
Yuri Kotov, Saint Petersburg (RU); and Andrey Markov, Saint Petersburg (RU)
Assigned to Dell Products L.P., Hopkinton, MA (US)
Filed by EMC IP HOLDING COMPANY LLC, Hopkinton, MA (US)
Filed on May 3, 2021, as Appl. No. 17/246,761.
Prior Publication US 2022/0350711 A1, Nov. 3, 2022
Int. Cl. G06F 7/00 (2006.01); G06F 17/00 (2019.01); G06F 11/14 (2006.01); G06F 16/176 (2019.01); G06F 16/178 (2019.01); G06F 16/188 (2019.01); G06F 16/182 (2019.01)
CPC G06F 11/1469 (2013.01) [G06F 16/178 (2019.01); G06F 16/1774 (2019.01); G06F 16/183 (2019.01); G06F 16/188 (2019.01); G06F 2201/815 (2013.01)] 9 Claims
OG exemplary drawing
 
1. A virtual tape library system, comprising:
a primary virtual tape server comprising a non-transitory memory with program code configured to:
select an active copy of a shared locking filesystem from a plurality of copies of the shared locking filesystem, the active copy of the shared locking filesystem and the plurality of copies of the shared locking filesystem each being stored on different non-volatile drives;
receive tape drive utility access commands;
responsive to the tape drive utility access commands, use the active copy of the shared locking filesystem to generate corresponding input-output commands to access storage resources; and
a plurality of secondary virtual tape servers comprising non-transitory memory with program code configured to:
receive tape drive utility access commands;
responsive to the tape drive utility access commands, use the active copy of the shared locking filesystem selected by the primary virtual tape server to generate corresponding input-output commands to access storage resources; and
signal to the primary virtual tape server responsive to the active copy of the shared locking filesystem becoming unreachable from the non-volatile drive on which the active copy of the shared locking filesystem is stored, the signaling prompting one of the plurality of copies of the shared locking filesystem to replace the active copy of the shared locking filesystem to generate input-output commands to access storage resources;
wherein ones of the secondary virtual tape servers are configured to signal that the active copy of the shared locking filesystem has become unreachable by posting a synchronization request to at least one of the copies of the shared locking filesystem that is reachable;
wherein the primary virtual tape server is responsive to the synchronization request to post status request messages to all reachable copies of the shared locking filesystem; and
wherein the secondary virtual tape servers are responsive to the status request messages to post status messages to reachable copies of the shared locking filesystem indicating availability, including use as the active copy of the shared locking filesystem.