Creating and using a VDO volume
To create a VDO device, we will make use of the loopback device we created in Chapter 12, Managing Local Storage and Filesystems, so we will check first whether it’s mounted or not by executing this:
mount|grep loop
If there’s output, we might need to run umount /dev/loop0p1 (or relevant mounted filesystems); if no output is shown, we’re set for creating our vdo volume on top of it. Note that we should have a volume with enough space for this test, in this case, we’re using a 10 GB file to simulate a disk.
Since RHEL8, VDO has been integrated into the LVM, so for creating a VDO volume, we’ll need to prepare our loop device to be a physical volume with a volume group, which can be done with the following commands:
pvcreate /dev/loop0 vgcreate vdo /dev/loop0 lvcreate --type vdo --name myvdo vdo -L 20G
The output is shown in the following screenshot: