[lxc-users] Trouble starting LXD when LXD_DIR is on a ZFS pool.

[Daniel Gray]

I'm using Alpine Linux in diskless mode.

As a result the only persistent directory is my /etc, where the files
are tar'ed /media/usb/host.apkovl.tar.gz these configs are merged into
the system on reboot, and / is in tempfs.

I want to store my LXD_DIR on a ZFS dataset. This storage will be
persistent.

I've noticed that the LXD service won't start if I try to do so. The
error seems to be related to the failure to create:

srwx------ 1 root root 0 May 11 14:11 /var/lib/lxd/seccomp.socket
srw-rw---- 1 root root 0 May 11 14:11 /var/lib/lxd/unix.socket

I've already created a zpool with two datasets:

# zfs list
NAME               USED  AVAIL     REFER  MOUNTPOINT
POOL              8.37M  50.1T      239K  /mnt/data
POOL/lxd           759K  50.1T      759K  /var/lib/lxd
POOL/lxd_storage   341K  50.1T      341K  /mnt/data/lxd_storage

# zfs mount POOL/lxd
# chmod 755 /var/lib/lxd

Then I try to start lxd:

Error: Failed to create dqlite server: raft_init(): io: create I/O
capabilities probe file: posix_allocate: operation not supported on
socket

If anyone has any other suggestions about how I should set this up in
relation to my pool, I'm open to suggestions.

The requirement is that POOL/lxd and POOL/lxd_storage be encrypted, and
for that I used:

# zfs create \
        -o encryption=aes-256-gcm \
        -o keyformat=raw \
        -o keylocation=file:///mnt/mount/lxd \
        -o mountpoint=/var/lib/lxd \
        pool/lxd

# zfs create \
        -o encryption=aes-256-gcm \
        -o keyformat=raw \
        -o keylocation=file:///mnt/mount/lxd \
        pool/lxd_storage

I mount my encrypted storage, load my keys with:

# zfs load-keys -a

and then proceed to start lxd, manually. The idea is that if a power
loss occurs the lxd containers cannot be accessed until I provide my
keys.

-- 
Daniel Gray (dng) 0x41911F722B0F9AE3