20.3. Removing block devices and associated metadata

Procedure

1. Unmount the file system:

   # umount /mnt/mount-point

2. Remove the file system:

   # wipefs -a /dev/vg0/myvol

   If you have added an entry into the /etc/fstab file to make a persistent association between the file system and a mount point, edit /etc/fstab at this point to remove that entry.

   Continue with the following steps, depending on the type of the device you want to remove:

3. Remove the logical volume (LV) that contained the file system:

   # lvremove vg0/myvol

4. If there are no other logical volumes remaining in the volume group (VG), you can safely remove the VG that contained the device:

   # vgremove vg0

5. Remove the physical volume (PV) metadata from the PV device(s):

   # pvremove /dev/sdc1

   # wipefs -a /dev/sdc1

6. Remove the partitions that contained the PVs:

   # parted /dev/sdc rm 1

7. Remove the partition table if you want to fully wipe the device:

   # wipefs -a /dev/sdc

8. Execute the following steps only if you want to physically remove the device:

   • If you are removing a multipath device, execute the following commands:

     1. View all the paths to the device:

        # multipath -l

        The output of this command is required in a later step.

     2. Flush the I/O and remove the multipath device:

        # multipath -f multipath-device

   • If the device is not configured as a multipath device, or if the device is configured as a multipath device and you have previously passed I/O to the individual paths, flush any outstanding I/O to all device paths that are used:

     # blockdev --flushbufs device

     This is important for devices accessed directly where the umount or vgreduce commands do not flush the I/O.

   • If you are removing a SCSI device, execute the following commands:

     1. Remove any reference to the path-based name of the device, such as /dev/sd, /dev/disk/by-path, or the major:minor number, in applications, scripts, or utilities on the system. This ensures that different devices added in the future are not mistaken for the current device.

     2. Remove each path to the device from the SCSI subsystem:

        # echo 1 > /sys/block/device-name/device/delete

        Here the device-name is retrieved from the output of the multipath -l command, if the device was previously used as a multipath device.

9. Remove the physical device from a running system. Note that the I/O to other devices does not stop when you remove this device.