Issue

• SCSI Reservations are causing multipath to fail even if there is no issue with underlying storage devices.
  This issue is present only with kernel versions older than kernel-3.10.0-693.el7.

• Numerous scsi devices failing and path flapping errors recorded during SCSI persistence reservations events on multipath device:

  Dec 11 11:56:33 server1 kernel: sd 12:0:0:14: reservation conflict
  Dec 11 11:56:33 server1 kernel: sd 12:0:0:14: [sdar] tag#1 FAILED Result: hostbyte=DID_OK driverbyte=DRIVER_OK
  Dec 11 11:56:33 server1 kernel: sd 12:0:0:14: [sdar] tag#1 CDB: Write(10) 2a 00 59 fd ae 38 00 00 10 00
  Dec 11 11:56:33 server1 kernel: blk_update_request: critical nexus error, dev sdar, sector 1509797432
  Dec 11 11:56:33 server1 kernel: [416008.400797] device-mapper: multipath: Failing path 66:176.
  Dec 11 11:56:33 server1 kernel: device-mapper: multipath: Failing path 66:176.
  Dec 11 11:56:33 server1 multipathd: sdar: mark as failed
  Dec 11 11:56:33 server1 multipathd: 360000970000297500087533030303533: remaining active paths: 3 
  [...]
  Dec 11 11:56:33 server1 multipathd: 360000970000297500087533030303533: remaining active paths: 2