guest os boot stuck with mount operation error

[Nikola Krzalic]

I'm trying to migrate an OS running on a physical machine to an LXC container, but no luck so far. Right now the system gets stuck somewhere during lxc-start:
<...>

 * Stopping cgroup management proxy ...done.
 * Starting load modules from /etc/modules ...done.
 * Stopping Mount network filesystems ...done.
 * Starting set sysctls from /etc/sysctl.conf ...done.
 * Stopping set sysctls from /etc/sysctl.conf ...done.
 * Stopping load modules from /etc/modules ...done.
 * Starting configure network device ...done.
 * Starting Bridge socket events into upstart ...done.

<hangs indefinitely here>

Both host and guest are running ubuntu 14.04 LTS and same guest boots properly via VirtualBox... kern.log shows some issues with mounts:

Oct 7 10:35:45 ares kernel: [138643.960789] device veth0RG5HU entered promiscuous mode
Oct 7 10:35:45 ares kernel: [138643.961450] IPv6: ADDRCONF(NETDEV_UP): veth0RG5HU: link is not ready
Oct 7 10:35:45 ares kernel: [138643.987832] EXT4-fs (dm-5): couldn't mount as ext3 due to feature incompatibilities
Oct 7 10:35:45 ares kernel: [138643.987967] EXT4-fs (dm-5): couldn't mount as ext2 due to feature incompatibilities
Oct 7 10:35:45 ares kernel: [138643.988322] EXT4-fs (dm-5): mounted filesystem with ordered data mode. Opts: (null)
Oct 7 10:35:45 ares kernel: [138644.002660] IPv6: ADDRCONF(NETDEV_CHANGE): veth0RG5HU: link becomes ready
Oct 7 10:35:45 ares kernel: [138644.002702] lxcbr0: port 1(veth0RG5HU) entered forwarding state
Oct 7 10:35:45 ares kernel: [138644.002719] lxcbr0: port 1(veth0RG5HU) entered forwarding state
Oct 7 10:35:46 ares kernel: [138644.340780] type=1400 audit(1412670946.254:113): apparmor="DENIED" operation="mount" info="failed type match" error=-13 profile="lxc-container-default" name="/run/cgmanager/fs/none,name=systemd/" pid=399 comm="cgmanager" fstype="cgroup" srcname="none,name=systemd" flags="rw"
Oct 7 10:36:00 ares kernel: [138659.015558] lxcbr0: port 1(veth0RG5HU) entered forwarding state

Here is the container's configuration file:
lxc.include = /usr/share/lxc/config/ubuntu.common.conf

lxc.network.type = veth
lxc.network.flags = up
lxc.network.link = lxcbr0
lxc.utsname = myvm

lxc.autodev = 1
lxc.tty = 4
lxc.pts = 1024
lxc.rootfs = /dev/mapper/ubuntu--vmvg-lvroot
lxc.arch = x86_64
lxc.cap.drop = sys_module mac_admin

#lxc.aa_profile = lxc-container-default-with-mounting
lxc.cgroup.devices.deny = a
# Allow any mknod (but not using the node)
lxc.cgroup.devices.allow = c *:* m
lxc.cgroup.devices.allow = b *:* m
# /dev/null and zero
lxc.cgroup.devices.allow = c 1:3 rwm
lxc.cgroup.devices.allow = c 1:5 rwm
# consoles
lxc.cgroup.devices.allow = c 5:1 rwm
lxc.cgroup.devices.allow = c 5:0 rwm
#lxc.cgroup.devices.allow = c 4:0 rwm
#lxc.cgroup.devices.allow = c 4:1 rwm
# /dev/{,u}random
lxc.cgroup.devices.allow = c 1:9 rwm
lxc.cgroup.devices.allow = c 1:8 rwm
lxc.cgroup.devices.allow = c 136:* rwm
lxc.cgroup.devices.allow = c 5:2 rwm
# rtc
lxc.cgroup.devices.allow = c 254:0 rwm
#fuse
lxc.cgroup.devices.allow = c 10:229 rwm
#tun
lxc.cgroup.devices.allow = c 10:200 rwm
#full
lxc.cgroup.devices.allow = c 1:7 rwm
#hpet
lxc.cgroup.devices.allow = c 10:228 rwm
#kvm
lxc.cgroup.devices.allow = c 10:232 rwm
#lxc.cgroup.devices.allow = b 7:* rwm

Any suggestions?

[Serge Hallyn (serge-hallyn)]

Thanks for reporting this bug. To fix the cgmanager issue, add the line

lxc.mount.auto = cgroup:mixed

to your container configuration file.

That shouldn't explain your hang however. Assuming it doesn't, please run

lxc-start -n <container> -l trace -o debug.out -- /sbin/init debug verbose --debug --verbose

And append both the console output and the file debug.out

 status: incomplete

[Launchpad Janitor (janitor)]

[Expired for lxc (Ubuntu) because there has been no activity for 60 days.]