[lxc-users] unprivileged LXC and lxc-attach...

[Serge E. Hallyn]

Quoting Dirk Geschke (dirk at lug-erding.de):
> Hi Serge,
> 
> > No, I'm afraid you're being misled.  You simply can't strace lxc-attach.
> 
> ah, ok...
> 
> > Better to do
> > 
> > 	lxc-attach -l trace -o debugout -n containername
> > 
> > and look at (or mail here) the contents of the file debugout.
> 
> Now I get two error messages:
> 
>    lxc_cgfs - cgroups/cgfs.c:lxc_cgroupfs_attach:2538 - could not move attached process 22869 to cgroup of container
>    lxc_attach - attach.c:lxc_attach:992 - Expected to receive sequence number 0: No such file or directory.

Ok, if you look at the source, that message is a bit misleading - lxc
never got around to trying to move the task into the cgroup, it failed
to load a suitable set of cgroups data in the first place.

You really should be using cfsng, not cgfs.  Can you show your
cgroup layout?  (cat /proc/self/cgroup and mount | grep cgroup)

It might help if you set the lxc.cgroup.use in your personal
lxc.system.conf (~/.config/lxc/lxc.conf) to only include the cgroups
your container needs -  just freezer is the bare minimum.  That might
get your container running without switching to cgfsng.

-serge