HP MSA 1040 HP MSA 1040 SMU Reference Guide (762784-001, March 2014) - Page 89

Examples of when quarantine can occur are: • At system power-up, a vdisk has fewer disks online than at the previous power-up. This may happen because a disk is slow to spin up or because an enclosure is not powered up. The vdisk will be automatically dequarantined if the inaccessible disks come online and the vdisk status becomes FTOL (fault tolerant and online), or if after 60 seconds the vdisk status is QTCR or QTDN. • During system operation, a vdisk loses redundancy plus one more disk; for example, three disks are inaccessible in a RAID-6 vdisk or two disks are inaccessible for other fault-tolerant RAID levels. The vdisk will be automatically dequarantined if after 60 seconds the vdisk status is FTOL, FTDN, or CRIT. Quarantine isolates the vdisk from host access and prevents the system from changing the vdisk status to OFFL (offline). The number of inaccessible disks determines the quarantine status; from least to most severe: • QTDN (quarantined with a down disk): The RAID-6 vdisk has one inaccessible disk. The vdisk is fault tolerant but degraded. If the inaccessible disks come online or if after 60 seconds from being quarantined the vdisk is QTCR or QTDN, the vdisk is automatically dequarantined. • QTCR (quarantined critical): The vdisk is critical with at least one inaccessible disk. For example, two disks are inaccessible in a RAID-6 vdisk or one disk is inaccessible for other fault-tolerant RAID levels. If the inaccessible disks come online or if after 60 seconds from being quarantined the vdisk is QTCR or QTDN, the vdisk is automatically dequarantined. • QTOF (quarantined offline): The vdisk is offline with multiple inaccessible disks causing user data to be incomplete, or is an NRAID or RAID-0 vdisk. When a vdisk is quarantined, its disks become write-locked, its volumes become inaccessible, and it is not available to hosts until it is dequarantined. If there are interdependencies between the quarantined vdisk's volumes and volumes in other vdisks, quarantine may temporarily impact operation of those other volumes. For example, if the quarantined vdisk contains the snap pool used for snapshot, volume-copy, or replication operations, quarantine may temporarily cause the associated master volume to go offline; a volume-copy or replication operation can also be disrupted if an associated volume (snap pool, source volume, or destination volume) goes offline. Depending on the operation, the length of the outage, and the settings associated with the operation, the operation may automatically resume when the vdisk is dequarantined or may require manual intervention. A vdisk can remain quarantined indefinitely without risk of data loss. A vdisk is dequarantined when it is brought back online, which can occur in three ways: • If the inaccessible disks come online, making the vdisk FTOL, the vdisk is automatically dequarantined. • If after 60 seconds from being quarantined the vdisk is QTCR or QTDN, the vdisk is automatically dequarantined. The inaccessible disks are marked as failed and the vdisk status changes to CRIT (critical) or FTDN (fault tolerant with a down disk). If the inaccessible disks later come online, they are marked as LEFTOVR (leftover). • The dequarantine command is used to manually dequarantine the vdisk. If the inaccessible disks later come online, they are marked as LEFTOVR (leftover). If event 485 was logged, use the dequarantine command only as specified by the event's recommended-action text to avoid data corruption or loss. A quarantined vdisk can be fully recovered if the inaccessible disks are restored. Make sure that all disks are properly seated, that no disks have been inadvertently removed, and that no cables have been unplugged. Sometimes not all disks in the vdisk power up. Check that all enclosures have restarted after a power failure. If these problems are found and then fixed, the vdisk recovers and no data is lost. If the inaccessible disks cannot be restored (for example, they failed), and the vdisk's status is FTDN or CRIT, and compatible spares are available, reconstruction will automatically begin. If a replacement disk (reconstruct target) is inaccessible at power up, the vdisk becomes quarantined; when the disk is found, the vdisk is dequarantined and reconstruction starts. If reconstruction was in process, it continues where it left off. NOTE: The only tasks allowed for a quarantined vdisk are Dequarantine Vdisk and Delete Vdisk. If you delete a quarantined vdisk and its inaccessible disks later come online, the vdisk will reappear as quarantined or offline and you must delete it again (to clear those disks). Removing a vdisk from quarantine 89