[lxc-users] Regression in ephemeral containers

[overlay fs]

This issue arises from a bug in the overlayfs component of ubuntu's
linux-3.13 kernel.  The bug has been fixed in mainline linux-4.2 and
has been backported to ubuntu's linux-3.19, but not to linux-3.13.

bug report: https://bugs.launchpad.net/ubuntu/+source/lxc/+bug/1507463

On Mon, Oct 12, 2015 at 10:34 PM, overlay fs <overlayfs at gmail.com> wrote:
> Regression
> ---------------
> It is no longer possible to bind-mount a file into an ephemeral
> container, using the version of lxc in the lxc-daily ppa.  This used
> to work; the regression was introduced some time after September 15.
>
> Details
> ---------
> If the following entry is added to the config file of an ubuntu-14.04
> container named 'trusty',
>
>    lxc.mount.entry = /home/oleg/test.txt home/ubuntu/test.txt none
> bind,create=file 0 0
>
> then lxc-start works ok,
>
>    lxc-start -d -n trusty
>
> but lxc-start-ephemeral fails to start,
>
>    lxc-start-ephemeral -d -o trusty -n debug
>
> The error message in the logfile is,
>
>    lxc_utils - utils.c:safe_mount:1641 - Invalid argument - Failed to
> mount /home/oleg/test.txt onto
> /usr/lib/x86_64-linux-gnu/lxc/home/ubuntu/test.txt
>    lxc_conf - conf.c:mount_entry:1731 - Invalid argument - failed to
> mount '/home/oleg/test.txt' on
> '/usr/lib/x86_64-linux-gnu/lxc/home/ubuntu/test.txt'
>    lxc_conf - conf.c:lxc_setup:3762 - failed to setup the mount
> entries for 'debug'    lxc_start - start.c:do_start:722 - failed to
> setup the container