This change is a precursor to switching the default Docker storage
driver to overlay2.
Previously, Kayobe's default configuration included a 'data' LVM volume
group, with a 'docker-volumes' logical volume mounted at
/var/lib/docker/volumes. Additionally, if the Docker devicemapper
storage driver was used, the data volume group would contain the
docker-thinpool and docker-thinpoolmeta volumes.
This LVM setup was really included for devicemapper, and while in some
cases it may be useful to have docker volumes as a separate logical
volume, this doesn't really make sense as a default. Often in
environments using other Docker storage drivers, the data volume group
would be removed from configuration.
This change modifies the default LVM configuration to only create a
'data' volume group if the Docker storage driver is devicemapper.
Additionally, new flags are added to make this choice independent from
the storage driver, to support cases where the data volume group is
required without devicemapper.
Change-Id: Ia3c1f6423c32fa2580b57db32512a34ce35d7acc
Story: 2005667
Task: 30973
1d8b4e2500