Hi:I downloaded a cirros-0.3.0-x86_64-rootfs.img and mount it to /tmp/bak then I edit a xml file ,here is the content: <domain type='lxc'> <name>vm1</name> <memory>500000</memory> <os> <type>exe</type> <init>/bin/sh</init> </os> <vcpu>1</vcpu> <clock offset='utc'/> <on_poweroff>destroy</on_poweroff> <on_reboot>restart</on_reboot> <on_crash>destroy</on_crash> <devices> <emulator>/usr/libexec/libvirt_lxc</emulator> <filesystem type='mount'> <source dir='/tmp/bak'/> <target dir='/'/> </filesystem> <interface type='network'> <source network='default'/> </interface> <console type='pty' /> </devices> </domain> I defined it and no error , but when I start it , it comes with error: Failed to start domain vm1 error: internal error guest failed to start: 2012-10-24 13:08:14.684+0000: 16935: info : libvirt version: 0.9.10, package: 21.el6_3.4 (CentOS BuildSystem <http://bugs.centos.org>, 2012-08-23-18:28:26, c6b9.bsys.dev.centos.org) 2012-10-24 13:08:14.684+0000: 16935: error : lxcControllerRun:1484 : Failed to query file context on /tmp/bak: No data available here is the ls -al /tmp/bak total 92 drwxr-xr-x 21 root root 4096 Oct 24 20:43 . drwxrwxrwt. 5 root root 4096 Oct 24 21:08 .. drwxr-xr-x 2 root root 4096 Oct 24 20:43 bin drwxr-xr-x 3 root root 4096 Oct 24 20:43 boot drwxr-xr-x 3 root root 4096 Oct 24 20:43 dev drwxr-xr-x 7 root root 4096 Oct 24 20:43 etc drwxr-xr-x 4 root root 4096 Oct 24 20:43 home -rwxr-xr-x 1 root root 2785 Oct 24 20:43 init lrwxrwxrwx 1 root root 32 Oct 24 20:43 initrd.img -> boot/initrd.img-3.0.0-12-virtual drwxr-xr-x 4 root root 4096 Oct 24 20:43 lib lrwxrwxrwx 1 root root 11 Oct 24 20:43 linuxrc -> bin/busybox drwx------ 2 root root 4096 Oct 24 20:43 lost+found drwxr-xr-x 2 root root 4096 Oct 24 20:43 mnt drwxr-xr-x 2 root root 4096 Oct 24 20:43 .oldroot drwxr-xr-x 2 root root 4096 Oct 24 20:43 old-root drwxr-xr-x 2 root root 4096 Oct 24 20:43 opt drwxr-xr-x 2 root root 4096 Oct 24 20:43 proc drwx------ 2 root root 4096 Oct 24 20:43 root drwxr-xr-x 2 root root 4096 Oct 24 20:43 run drwxr-xr-x 2 root root 4096 Oct 24 20:43 sbin drwxr-xr-x 2 root root 4096 Oct 24 20:43 sys drwxr-xr-t 3 root root 4096 Oct 24 20:43 tmp drwxr-xr-x 6 root root 4096 Oct 24 20:43 usr drwxr-xr-x 8 root root 4096 Oct 24 20:43 var lrwxrwxrwx 1 root root 29 Oct 24 20:43 vmlinuz -> boot/vmlinuz-3.0.0-12-virtual How can I solve this problem? Thanks :-)