Unmount an NVMe Storage Drive

Language:

Log in to Oracle Linux that is running on the server.
Remove the NVMe storage device path.
1. To find the PCIe addresses (Bus Device Function), type:
  # find /sys/devices |egrep ‘nvme[0-9][0-9]?$’
  
  This commands returns output similar to the following:
```
/sys/devices/pci0000:80/0000:80:03.0/0000:b0:00.0/0000:b1:04.0/0000:b2:00.0/misc/nvme0
/sys/devices/pci0000:80/0000:80:03.0/0000:b0:00.0/0000:b1:05.0/0000:b4:00.0/misc/nvme1
```
  In the above listing the PCIe addresses are highlighted in bold text.
2. To obtain the slot number (APIC ID) for the bus address, type the following command to list all of the PCIe slot numbers and the corresponding bus addresses:
  # egrep –H ‘.*’ /sys/bus/pci/slots/*/address
  
  This commands returns output similar to the following:
```
    /sys/bus/pci/slots/10/address:0000:b8:00
    /sys/bus/pci/slots/11/address:0000:b6:00
    /sys/bus/pci/slots/12/address:0000:b2:00 (instance nvme0, pcie slot 12, drive label nvme2)
    /sys/bus/pci/slots/13/address:0000:b4:00 (instance nvme1, pcie slot 13, drive label nvme3)
```
  In the above output, the bus addresses for the corresponding NVMe instances are highlighted in bold text.
  
  Note - In the above output, notice that the instance names for the NVMe drives do not correspond to the NVMe drive labels on the front of the server, that is, pci/slots/12/address: 0000:b2:00 corresponds to instance nvme0; however, on the front of the server, this drive is labeled NVMe2. For a table that shows the relationship between the pci/slot# and the NVMe storage drive label on the front of the server, see Server Operating System Names for the NVMe Storage Drives.
3. Disconnect all users of the NVMe drive and back up the NVMe drive data as needed.
  1. Use the umount command to unmount any file systems that are mounted on the device.
  2. Remove the device from any multiple device (md) and Logical Volume Manager (LVM) volume using it.
    If the device is a member of an LVM Volume group, then it might be necessary to move data off the device using the pvmove command, then use the vgreduce command to remove the physical volume, and (optionally) pvremove to remove the LVM metadata from the disk.
  3. If the device uses multipathing, run multipath -l and note all the paths to the device. Then, remove the multipathed device using the multipath -f device command.
  4. Run the blockdev --flushbufs device command to flush any outstanding I/O to all paths to the device.
To prepare the NVMe drive for removal, that is, to detach the NVMe device driver and power off the NVMe drive slot, type:
# echo 0 > /sys/bus/pci/slots/$slot/power

Where $slot is the slot number obtained in step Step 2.b above.
Verify that the OK to Remove indicator (LED) on the NVMe drive is lit.