3.5. Creating an LVM-VDO volume

Procédure

1. Pick a name for your VDO LV, such as vdo1. You must use a different name and device for each VDO LV on the system.

   In all the following steps, replace vdo-name with the name.

2. Create the VDO LV:

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   # lvcreate --type vdo \
              --name vdo-name
              --size physical-size
              --virtualsize logical-size \
              vg-name

   • Replace vg-name with the name of an existing LVM volume group where you want to place the VDO LV.
   • Replace logical-size with the amount of logical storage that the VDO LV will present.

   • If the physical size is larger than 16TiB, add the following option to increase the slab size on the volume to 32GiB:

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     --config 'allocation/vdo_slab_size_mb=32768'

     If you use the default slab size of 2GiB on a physical size larger than 16TiB, the lvcreate command fails with the following error:

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     ERROR - vdoformat: formatVDO failed on '/dev/device': VDO Status: Exceeds maximum number of slabs supported

     Exemple 3.1. Creating a VDO LV for container storage

     For example, to create a VDO LV for container storage on a 1TB VDO pool LV, you can use:

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     # lvcreate --type vdo \
                --name vdo1
                --size 1T
                --virtualsize 10T \
                vg-name

     Important

     If a failure occurs when creating the VDO volume, remove the volume to clean up.

3. Create a file system on the VDO LV:

   • For the XFS file system:

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     # mkfs.xfs -K /dev/vg-name/vdo-name

   • For the ext4 file system:

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     # mkfs.ext4 -E nodiscard /dev/vg-name/vdo-name