Working with a Logical Volume Manager

The Logical Volume Manager creates symbolic links to each logical volume's block device, from a directory path in the form:

/dev/<volume group>/<volume name>

HPE Ezmeral Data Fabric needs the actual block location, which you can find by using the ls -l command to list the symbolic links.

1. Make sure you have free, unmounted logical volumes for use by HPE Ezmeral Data Fabric:
   • Unmount any mounted logical volumes that can be erased and used for HPE Ezmeral Data Fabric.
   • Allocate any free space in an existing logical volume group to new logical volumes.
2. Make a note of the volume group and volume name of each logical volume.
3. Use ls -l with the volume group and volume name to determine the path of each logical volume's block device. Each logical volume is a symbolic link to a logical block device from a directory path that uses the volume group and volume name:

   /dev/<volume group>/<volume name>

   The following example shows output that represents a volume group named mapr containing logical volumes named mapr1, mapr2, mapr3, and mapr4:

   ls -l /dev/mapr/mapr*
    lrwxrwxrwx 1 root root 22 Apr 12 21:48 /dev/mapr/mapr1 -> /dev/mapper/mapr-mapr1
    lrwxrwxrwx 1 root root 22 Apr 12 21:48 /dev/mapr/mapr2 -> /dev/mapper/mapr-mapr2
    lrwxrwxrwx 1 root root 22 Apr 12 21:48 /dev/mapr/mapr3 -> /dev/mapper/mapr-mapr3
    lrwxrwxrwx 1 root root 22 Apr 12 21:48 /dev/mapr/mapr4 -> /dev/mapper/mapr-mapr4

4. Create a text file /tmp/disks.txt containing the paths to the block devices for the logical volumes (one path on each line). Example:

   cat /tmp/disks.txt
    /dev/mapper/mapr-mapr1
    /dev/mapper/mapr-mapr2
    /dev/mapper/mapr-mapr3
    /dev/mapper/mapr-mapr4

5. Pass disks.txt to disksetup.