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Known issues with NVMe surprise removal
12 NVMe Surprise Removal on Dell EMC PowerEdge servers running Linux operating systems | 451
3.3.3 Status of the RAID 0 logical volume is displayed as Available when one of the
members of the RAID array is surprise removed
Description: When Logical Volume Manager (LVM) is used to create a RAID 0 array and a member of the
RAID array is surprise removed, the lvdisplay command shows the logical volume (LV) status as
‘Available’.
Solution: Use the command lvs -o +lv_health_status to check the status of the RAID array. The
command displays the output Partial when a member of the RAID array is removed.
3.3.4 /proc/mdstat and mdadm -D commands display incorrect statuses when two
NVMe devices are surprise removed from a RAID 5 MD array
Description: When two of three NVMe devices are surprise removed from a RAID 5 MD array, the command
cat/proc/mdstat displays the array status incorrectly as active. Similarly, when the status of the MD
RAID is queried using the mdadm -D /dev/mdN command, the number of active and working devices
displayed is two. Only the status of the array reported is incorrect however, when I/O operations are
performed, I/O errors are observed as expected.
Cause: When the number of devices that are surprise removed exceeds the number of devices that are
required for the array to function, the MD status is not updated.