[lxc-users] LXD - unable to copy container from 2.08 to 2.12 using BTRFS

[Ron Kelley]

Greetings all.

I have two LXD servers: server(a) is running 2.08 and server(b) is running 2.12.  Both servers have BTRFS filesystems.  I am trying to copy/migrate a container from server(a) to server(b) but keep running into LXD issues:


root at WP-Container-Mgmt:~# lxc stop WP-Container-004:wordpress-testsite-com1  && copy WP-Container-004:wordpress-testsite-com1 WP-Container-005:
(works OK)

On the receiving side, I see a similar directory with a timestamp:
-------------------------------
root at HJ-WP-Container-005: ls -la /var/lib/lxd/storage-pools/default/containers 
drwxr-xr-x 1 root   root   132 May 15 22:46 .
drwxr-xr-x 1 root   root    62 Apr 28 09:34 ..
drwx------ 1 root   root    10 May 15 22:46 wordpress-testsite-com1845325915


…and, inside that site directory I see this:
-----------------------------
root at HJ-WP-Container-005: ls -la /var/lib/lxd/storage-pools/default/containers/wordpress-testsite-com1845325915/
total 0
drwx------  1 root   root    10 May 15 22:46 .
drwxr-xr-x  1 root   root   132 May 15 22:46 ..
drwxr-xr-x+ 1 100000 100000  12 May 15 22:49 .root


Running an “lxc list”, I see this:
-----------------------------
root at HJ-WP-Container-005:/var/lib/lxd/storage-pools/default/containers# lxc list
+--------------------------+---------+--------------------------------+------+------------+-----------+
|           NAME           |  STATE  |              IPV4              | IPV6 |    TYPE    | SNAPSHOTS |
+--------------------------+---------+--------------------------------+------+------------+-----------+
| wordpress-testsite-com1  | STOPPED |                                |      | PERSISTENT | 0         |
+--------------------------+---------+--------------------------------+------+------------+-----------+


Trying to sort the container on the receiving side:
---------------------------------------------------
root at HJ-WP-Container-005:/var/lib/lxd/storage-pools/default/containers# lxc start wordpress-testsite-com
error: saving config file for the container failed
Try `lxc info --show-log wordpress-testsite-com` for more info
root at HJ-WP-Container-005:/var/lib/lxd/storage-pools/default/containers# lxc info --show-log wordpress-testsite-com
Name: wordpress-testsite-com
Remote: unix:/var/lib/lxd/unix.socket
Architecture: x86_64
Created: 2017/05/16 03:30 UTC
Status: Stopped
Type: persistent
Profiles: WP__Default

Log:



At this point, LXD is in an inconsistent state.  BTRFS now has a sub volume for this container (under container_name/.root), but LXC won’t allow me to remove it until I do some *hackery*
------------------------------------------------------------
root at HJ-WP-Container-005:/var/lib/lxd/storage-pools/default/containers# lxc delete wordpress-testsite-com1
error: Failed to run: btrfs subvolume delete /var/lib/lxd/storage-pools/default/containers/wordpress-testsite-com1: ERROR: cannot access subvolume /var/lib/lxd/storage-pools/default/containers/wordpress-testsite-com1: No such file or directory

btrfs sub list /var/lib/lxd/storage-pools/default/containers
---------------------------
ID 257 gen 1238 top level 5 path containers
ID 258 gen 1176 top level 5 path snapshots
ID 259 gen 229 top level 5 path images
ID 260 gen 12 top level 5 path custom
ID 1087 gen 1245 top level 257 path wordpress-testsite-com1845325915/.root


root at HJ-WP-Container-005:/var/lib/lxd/storage-pools/default/containers# btrfs sub del wordpress-testsite-com1845325915/.root/
Delete subvolume (no-commit): '/var/lib/lxd/storage-pools/default/containers/wordpress-testsite-com1845325915/.root’

root at HJ-WP-Container-005:/var/lib/lxd/storage-pools/default/containers# rmdir wordpress-testsite-com1845325915/

root at HJ-WP-Container-005:/var/lib/lxd/storage-pools/default/containers# btrfs sub create wordpress-testsite-com1
Create subvolume './wordpress-testsite-com1’

root at HJ-WP-Container-005:/var/lib/lxd/storage-pools/default/containers# lxc delete wordpress-testsite-com1



Obviously, there are a *few* bugs here, but I really need to get those containers from the 2.08 server to the 2.12 server.  What is the best way to make this happen?

-Ron