I see from the LXD storage specs that LVM can be used as a backingstore. I've previously managed to get LVM working with LXC. This was very pleasing, since it allows quota-style control of disk consumption.
How do I achieve this with LXD?
From what I understand, storage.lvm_vg_name must point to my volume
group. I've set this for a container by creating a profile, and
applying that profile to the container. The entire profile config
looks like this:
name: my-profile-name
config:
raw.lxc: |
storage.lvm_vg_name = lxc-volume-group
lxc.start.auto = 1
lxc.arch = amd64
lxc.network.type = veth
lxc.network.link = lxcbr0
lxc.network.flags = up
lxc.network.hwaddr = 00:16:3e:xx:xx:xx
lxc.cgroup.cpu.shares = 1
lxc.cgroup.memory.limit_in_bytes = 76895572
security.privileged: "false"
devices: {}
The volume group should be available and working, according to pvdisplay on the host box:
--- Physical volume ---
PV Name /dev/sdc5
VG Name lxc-volume-group
PV Size 21.87 GiB / not usable 3.97 MiB
Allocatable yes
PE Size 4.00 MiB
Total PE 5599
Free PE 901
Allocated PE 4698
PV UUID what-ever
However after applying the profile and starting the container, it appears to be using file backing store:
me@my-box:~# ls /var/lib/lxd/containers/container-name/rootfs/
bin boot dev etc home lib lib64 lost+found media mnt opt
proc root run sbin srv sys tmp usr var
What am I doing wrong?
Note that we also ship a python script with LXD to do the initial VG configuration for you.
As for disk quotas, we have a new specification for it which we'll be implementing shortly and that will let you set disk quotas for any storage attached to a container which supports it.
While we still support LVM, our main focus and preference as far as storage backend go is ZFS nowadays as it allows such changes to happen live and also works better when moving containers and snapshots across the network.
The new storage quota feature will be supported on zfs, LVM and btrfs but will only be applied live for zfs and btrfs, LVM will require a container restart.