[lxc-users] cgmanager: cgm_list_children for controller=systemd, cgroup_path=user failed: invalid request

[Serge Hallyn]

Quoting Smart Goldman (ytlec2014 at gmail.com):
> Hello.
> 
> I know about neither PAM nor cgmanager very well.
> But since my ubuntu server outputs a cgmanager-related error and I can not
> solve it myself, please allow me to ask a question.
> I apologize to you all if question about cgmanager is not allowed here.

cgmanager is an lxc project, so no worries.

> Ubuntu 14.04.1 LTS 64bit minimal is running as an OS on contracted VPS
> service by OpenVZ.
> The following error message is output to /var/log/auth.log by rebooting
> server.
> 
> /var/log/auth.log
> Jan 12 02:27:05 myhost systemd-logind[297]: cgmanager: cgm_list_children
> for controller=systemd, cgroup_path=user failed: invalid request
> Jan 12 02:27:05 myhost systemd-logind[297]: New seat seat0.
> Jan 12 02:27:06 myhost sshd[493]: Server listening on 0.0.0.0 port 22.
> Jan 12 02:27:06 myhost sshd[493]: Server listening on :: port 22.
> 
> It looks like it is output soon after installing cgroup-bin and
> cgmanager-utils.
> What is the cause of the problem?
> Or is this ignorable error message?

A few things - first, running cgroup-bin alongside cgmanager is
probably a bad idea.  Second, on 14.04 after install cgmanager
you unfortunately need to 'sudo restart systemd-logind', then
log out and log back in (or just ssh localhost) to get a new
cgroup.  After that you should be able to create unprivileged containers.

But it looks like that error message happened after you did that,
upon login?

The message may be ignorable - the real question is, when you
login, do you get a custom cgroup?  What does /proc/self/cgroup
show?