[lxc-users] lxc 2.0.7: sysvinit on the host breaks systemd based containers

[Serge E. Hallyn]

Quoting Harald Dunkel (harri at afaics.de):
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> On 04/03/17 07:03, Harald Dunkel wrote:
> > Hi folks,
> > 
> > using sysvinit-core on the host the systemd based containers get stuck in /sbin/init. lxc-attach shows:
> > 
> > root at lxcclient:~# ps -ef UID        PID  PPID  C STIME TTY          TIME CMD root         1     0  0 11:49 ?        00:00:00 /sbin/init root        24     0  0 12:05 pts/0    00:00:00 /bin/bash root        26    24  0 12:05 pts/0    00:00:00 ps -ef
> > 
> > This host uses lxc 2.0.7, as it can be found in Jessie backports. See below for a list of installed packages. The container was created on the same host.
> > 
> > I am bound to sysvinit-core on my HA systems. For lxc 1.1.5 there was no such problem, so I wonder if there is a workaround on the host?
> > 
> 
> PS: If I drop /cgroup from /etc/fstab on the host and reboot, then
> the problem seems to be gone.
> 
> Does this ring a bell?

Sounds like just systemd refusing to boot because all cgroups are comounted?
Are you sure that reverting to 1.1.5 fixes it, and it's not a newer systemd
breaking it?

One thought that comes to mind - perhaps in the past you used the lxcfs cgroup
bind mounts, and now you try to use the cgroup namespaces.  The lxcfs cgroup
mounts always created a filesystem per cgroup controller.

It would help to ask for more debugging information from systemd, 

    lxc.init_cmd = /sbin/init log_target=console log_level=debug

as well as looking at /sys/fs/cgroup in the container while systemd is
hung.