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Table of contents
3 NVMe Surprise Removal on Dell EMC PowerEdge servers running Linux operating systems | 451
Table of contents
Revisions............................................................................................................................................................................. 2
Acknowledgements ............................................................................................................................................................. 2
Table of contents ................................................................................................................................................................ 3
Executive summary ............................................................................................................................................................. 4
1 Introduction ................................................................................................................................................................... 5
1.1 Audience and scope ........................................................................................................................................... 5
1.2 Terminology ........................................................................................................................................................ 5
1.3 Command-line utilities used for verifying surprise removal of NVMe devices .................................................... 5
2 Surprise removal of NVMe devices .............................................................................................................................. 6
2.1 Supported and unsupported scenarios for surprise removal of NVMe devices ................................................. 6
2.2 Identifying the NVMe device slot and verifying surprise removal ....................................................................... 6
2.3 Platform and operating system support summary .............................................................................................. 7
3 Known issues with NVMe surprise removal ................................................................................................................. 9
3.1 SUSE Linux Enterprise Server Service Pack 2 .................................................................................................. 9
3.1.1 MD RAID layer is not notified of the surprise removal of Samsung NVMe devices ........................................... 9
3.1.2 Status of the RAID 0 logical volume is displayed as Available when one of the members of the RAID array is
surprise removed .......................................................................................................................................................... 9
3.1.3 LVM does not activate a free physical volume when one of the NVMe devices is surprise removed ............... 9
3.1.4 /proc/mdstat and mdadm -D commands display incorrect statuses when two NVMe devices are surprise
removed from a RAID 5 MD array .............................................................................................................................. 10
3.2 Red Hat Enterprise Linux 8.2 ........................................................................................................................... 10
3.2.1 Dmesg displays error messages when NVMe device is surprise removed ..................................................... 10
3.2.2 Status of the RAID 0 logical volume is displayed as Available when one of the members of the RAID array is
surprise removed ........................................................................................................................................................ 10
3.2.3 /proc/mdstat and mdadm -D commands display incorrect statuses when two NVMe devices are surprise
removed from a RAID 5 MD array .............................................................................................................................. 11
3.3 Ubuntu LTS 20.04.01 ....................................................................................................................................... 11
3.3.1 The name of the NVMe device may change when it is hot inserted after a surprise removal ......................... 11
3.3.2 NVMe devices are enumerated in namespace 2 when hot-inserted into the server after being surprise
removed ...................................................................................................................................................................... 11
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 ........................................................................................................................................................ 12
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 .............................................................................................................................. 12
4 Summary .................................................................................................................................................................... 13
5 References ................................................................................................................................................................. 14