After launching images:ubuntu-core/16 and running snap refresh inside the container, and a lengthy wait, the container stops. starting the container again it immediately stops. Log shows:
/sbin/init: .: line 43: can’t open ‘/initrd/scripts/ubuntu-core-rootfs’
Is there some config I could apply to support Core’s staged mounting of its various kernel and gadget snaps? I kind of expected it to ‘just work’ 
It should just work :-).
When I try this, I get
Setup snap "core" (5717) security profiles (phase 2)
which takes too long to complete.
You can follow the process with the following. This is my 10-minute output and I’ll let it take as much time as it needs.
root@mycore:~# snap changes
ID Status Spawn Ready Summary
1 Done 2018-10-14T16:58:45Z 2018-10-14T16:58:47Z Initialize system state
2 Error 2018-10-14T16:58:47Z 2018-10-14T16:58:47Z Initialize device
3 Done 2018-10-14T16:59:50Z 2018-10-14T16:59:58Z Refresh "pc" snap
4 Doing 2018-10-14T17:00:03Z - Refresh "core" snap
5 Done 2018-10-14T17:05:37Z 2018-10-14T17:05:38Z Initialize device
6 Doing 2018-10-14T17:08:45Z - Auto-refresh snap "pc-kernel"
root@mycore:~#
Do you get something different?
I posted this bug report,
OK, so I guess it’s expected that now is should just work? I still have the same issue here. Additionally, the image still appears to be tracking edge for the core snap (and pc/pc-kernel) - that said, I tried manually refreshing them individually back to stable and always ended up with an unusable container, whatever order I did that in. What am I missing?
I also get an unusable container.
Initially, the container is created but then you get an automated snap refresh that does not manage to update core.
You get an uncompression error that is mentioned earlier.
Still, the default channel is edge (last checked 4d ago).
For me it looks like it requests a restart, which doesn’t happen automatically, and if I manually restart, the container is then dead. Here’s how it plays out for me:
seffyroff@maas-controllers:~$ lxc exec testcore bash
root@testcore:~# snap changes
ID Status Spawn Ready Summary
1 Done 2018-10-21T16:42:28Z 2018-10-21T16:42:31Z Initialize system state
2 Error 2018-10-21T16:42:31Z 2018-10-21T16:42:32Z Initialize device
3 Done 2018-10-21T16:46:32Z 2018-10-21T16:46:32Z Switch "pc-kernel" snap to stable
4 Done 2018-10-21T16:46:38Z 2018-10-21T16:46:38Z Switch "pc" snap to stable
5 Done 2018-10-21T16:46:45Z 2018-10-21T16:46:45Z Switch "core" snap to stable
6 Done 2018-10-21T16:46:53Z 2018-10-21T16:47:10Z Refresh "pc-kernel" snap
7 Done 2018-10-21T16:47:16Z 2018-10-21T16:47:18Z Refresh "pc" snap
8 Doing 2018-10-21T16:47:25Z - Refresh "core" snap
9 Done 2018-10-21T16:47:31Z 2018-10-21T16:47:32Z Initialize device
root@testcore:~# snap tasks 8
Status Spawn Ready Summary
Done 2018-10-21T16:47:25Z 2018-10-21T16:47:25Z Ensure prerequisites for "core" are available
Done 2018-10-21T16:47:25Z 2018-10-21T16:47:30Z Download snap "core" (5662) from channel "stable"
Done 2018-10-21T16:47:25Z 2018-10-21T16:47:31Z Fetch and check assertions for snap "core" (5662)
Done 2018-10-21T16:47:25Z 2018-10-21T16:47:31Z Mount snap "core" (5662)
Done 2018-10-21T16:47:25Z 2018-10-21T16:47:31Z Run pre-refresh hook of "core" snap if present
Done 2018-10-21T16:47:25Z 2018-10-21T16:47:31Z Stop snap "core" services
Done 2018-10-21T16:47:25Z 2018-10-21T16:47:31Z Remove aliases for snap "core"
Done 2018-10-21T16:47:25Z 2018-10-21T16:47:32Z Make current revision for snap "core" unavailable
Done 2018-10-21T16:47:25Z 2018-10-21T16:47:32Z Copy snap "core" data
Done 2018-10-21T16:47:25Z 2018-10-21T16:47:32Z Setup snap "core" (5662) security profiles
Done 2018-10-21T16:47:25Z 2018-10-21T16:47:32Z Make snap "core" (5662) available to the system
Doing 2018-10-21T16:47:25Z - Setup snap "core" (5662) security profiles (phase 2)
Do 2018-10-21T16:47:25Z - Set automatic aliases for snap "core"
Do 2018-10-21T16:47:25Z - Setup snap "core" aliases
Do 2018-10-21T16:47:25Z - Run post-refresh hook of "core" snap if present
Do 2018-10-21T16:47:25Z - Start snap "core" (5662) services
Do 2018-10-21T16:47:25Z - Clean up "core" (5662) install
Do 2018-10-21T16:47:25Z - Run configure hook of "core" snap if present
......................................................................
Make snap "core" (5662) available to the system
2018-10-21T16:47:32Z INFO Requested system restart.
......................................................................
Setup snap "core" (5662) security profiles (phase 2)
2018-10-21T16:47:32Z INFO Waiting for restart...
root@testcore:~# reboot
root@testcore:~# seffyroff@maas-controllers:~$ lxc list
+----------+---------+------+------+------------+-----------+
| NAME | STATE | IPV4 | IPV6 | TYPE | SNAPSHOTS |
+----------+---------+------+------+------------+-----------+
| testcore | STOPPED | | | PERSISTENT | |
+----------+---------+------+------+------------+-----------+
seffyroff@maas-controllers:~$ lxc start testcore
seffyroff@maas-controllers:~$ lxc list
+----------+---------+------+------+------------+-----------+
| NAME | STATE | IPV4 | IPV6 | TYPE | SNAPSHOTS |
+----------+---------+------+------+------------+-----------+
| testcore | STOPPED | | | PERSISTENT | |
+----------+---------+------+------+------------+-----------+
seffyroff@maas-controllers:~$ lxc info --show-log testcore
Name: testcore
Location: none
Remote: unix://
Architecture: x86_64
Created: 2018/10/21 16:42 UTC
Status: Stopped
Type: persistent
Profiles: default
Log:
lxc testcore 20181021164846.372 WARN conf - conf.c:lxc_map_ids:2917 - newuidmap binary is missing
lxc testcore 20181021164846.373 WARN conf - conf.c:lxc_map_ids:2923 - newgidmap binary is missing
lxc testcore 20181021164846.408 WARN conf - conf.c:lxc_map_ids:2917 - newuidmap binary is missing
lxc testcore 20181021164846.408 WARN conf - conf.c:lxc_map_ids:2923 - newgidmap binary is missing
lxc testcore 20181021164846.475 WARN conf - conf.c:lxc_setup_devpts:1618 - Invalid argument - Failed to unmount old devpts instance
lxc testcore 20181021164847.664 WARN conf - conf.c:lxc_map_ids:2917 - newuidmap binary is missing
lxc testcore 20181021164847.664 WARN conf - conf.c:lxc_map_ids:2923 - newgidmap binary is missing
seffyroff@maas-controllers:~$Have a look at the GitHub issue.
There there is a mention on the compression problem with lzcat, and how to check whether you have it as well.