[lxc-users] failed to start container on centos

[Serge Hallyn]

Quoting Mingjiang Shi (mrjewes at gmail.com):
> Hi Alvaro,
> Thanks for your reply and suggestion.  It still doesn't work.
> 
> [root at devmachine rootfs]# service cgconfig status
> Running
> 
> [root at devmachine rootfs]# service libvirtd status
> libvirtd (pid  2671) is running...
> 
> [root at devmachine rootfs]# lxc-start -n c1 -d
> lxc-start: command get_cgroup failed to receive response
> 
> [root at devmachine rootfs]# lxc-start -n c1
> lxc-start: unknown capability mac_admin
> lxc-start: failed to drop capabilities
> lxc-start: failed to setup the container
> lxc-start: invalid sequence number 1. expected 2
> lxc-start: failed to spawn 'c1'
> 
> Any idea about this error message: "lxc-start: unknown capability
> mac_admin"?

Either your kernel is very old and doesn't support it, or your
header files are.

You might want to grab the libcap2 source
(https://www.kernel.org/pub/linux/libs/security/linux-privs/libcap2/),
build it, and do 'capsh --print'.  see if cap_admin shows up.

Actually, it looks like your package was built with
HAVE_SYS_CAPABILITY_H unset. You should install your libcap
headers and rebuild.

-serge