This change enhances the growvols script to support all volumes being
backed by one thin provisioning pool.
If a pool is detected, the following occurs:
- validation to confirm every volume is backed by the pool
- only the pool is extended into the new partition
- volumes are extended by the same amount as the non thin-provisioned
case
This results in no volumes being over-provisioned, so
out-of-space behaviour will be the same as the non thin-provisioned
case.
This change also switches to using /dev/mapper device mapper paths for
volume block devices, since that is the only path the thin pool is
mapped to.
Change-Id: I96085fc889e72c942cfef7e3acb6f6cd73f606dd
There is currently no automated way of growing LVM volumes on boot
like single partition images do with their growroot mechanism. This
lack likely contributes to LVM not being widely used on VM and
baremetal workloads, since growing to the full disk requires workload
knowledge to determine which volumes to grow and by what amount.
The growvols element contributes a growvols python script which can be
run on firstboot (via systemd or cloud-init) or manually via
automation such as ansible. It is also an interactive script which
displays the full list of modifying commands before prompting for
confirmation to run them all.
By default the script will grow the root volume, but arguments allow
any volume to grow by a specified amount, or a percentage of the
available disk space.
Blueprint: whole-disk-default
Change-Id: Idcf774384e56cce03e56c0e19c7d08a768606399
