[libvirt] Problems with <filesystem type='block'>

[Gao feng]

Hi Doug,

On 2013/03/04 12:38, Doug Goldstein wrote:
> On Sun, Mar 3, 2013 at 5:24 PM, Doug Goldstein <cardoe at gentoo.org> wrote:
>> On Fri, Dec 21, 2012 at 10:15 PM, Lars Kellogg-Stedman <lars at oddbit.com> wrote:
>>> Using libvirt 1.0.1, I'm trying to start an LXC container using the
>>> '<filesytem type="block">' syntax, like this:
>>>
>>>     <filesystem type="block" accessmode="passthrough">
>>>       <source dev="/dev/vg_files/vm-foobar-root" />
>>>       <target dir="/" />
>>>     </filesystem>
>>>
>>> The specified block device exists:
>>>
>>>     # ls -lL /dev/vg_files/vm-foobar-root
>>>     brw-rw---- 1 root disk 253, 19 Dec 21 22:23 /dev/vg_files/vm-foobar-root
>>>
>>> If I start the domain, it appears to start without any errors...
>>>
>>>     # virsh start foobar
>>>     Domain foobar started
>>>
>>> ...but it's not actually running.  The log files (with loglevel=2)
>>> don't seem to be very interesting; this is everything from the
>>> instance log file:
>>>
>>> 2012-12-22 04:10:57.862+0000: starting up
>>> PATH=/usr/local/sbin:/usr/local/bin:/usr/sbin:/usr/bin:/sbin:/bin LIBVIRT_DEBUG=2 LIBVIRT_LOG_OUTPUTS=2:stderr /usr/lib/libvirt/libvirt_lxc --name foobar --console 22 --security=none --handshake 25 --background --veth veth1
>>> 2012-12-22 04:10:57.967+0000: 1468: info : libvirt version: 1.0.1
>>> 2012-12-22 04:10:57.967+0000: 1468: info : lxcCapsInit:151 : No driver, not initializing security driver
>>> PATH=/bin:/sbin TERM=linux container=lxc-libvirt container_uuid=9041e32e-1df2-00c2-4660-dfa5b41510b7 LIBVIRT_LXC_UUID=9041e32e-1df2-00c2-4660-dfa5b41510b7 LIBVIRT_LXC_NAME=foobar /sbin/init
>>> 2012-12-22 04:10:58.198+0000: 1: warning : lxcContainerDropCapabilities:1788 : libcap-ng support not compiled in, unable to clear capabilities
>>> 2012-12-22 04:10:58.198+0000: 1493: warning : lxcControllerClearCapabilities:679 : libcap-ng support not compiled in, unable to clear capabilities
>>>
>>> Running an "strace" on the libvirtd process (strace -p <libvirtd_pid>
>>> -f ...), it doesn't look like libvirt is ever trying to mount the
>>> referenced filesystem.
>>>
>>> Is this supposed to work?  It seems like the support for having
>>> libvirt mount the block device is relatively recent, and I haven't had
>>> much luck finding examples of other folks using this capability.
>>>
>>> Thanks,
>>>
>>> -- Lars
>>
>> Lars,
>>
>> I just gave it a whirl. And I'm able to reproduce the same issue you
>> are seeing. The issue appears to be that
>> lxcContainerMountFsBlockAuto() is never being called. It was added in
>> http://www.redhat.com/archives/libvir-list/2011-August/msg00201.html
>> Hopefully I'll have more info soon.
>>
>> --
>> Doug Goldstein
> 
> It appears in the case of filesystem type=block the libvirt_lxc helper
> just gets wedged right away from first execution.
> 
> 2013-03-04 04:17:55.443+0000: 7197: debug : virFileMakePathHelper:1272 : path=/v
> ar/run/libvirt/lxc mode=0777
> 2013-03-04 04:17:55.443+0000: 7197: debug : virFileClose:72 : Closed fd 18
> 2013-03-04 04:17:55.443+0000: 7197: debug : virCommandRunAsync:2200 : About to r
> un PATH=/usr/local/sbin:/usr/local/bin:/usr/sbin:/usr/bin:/sbin:/bin:/opt/bin:/u
> sr/x86_64-pc-linux-gnu/gcc-bin/4.6.3 LIBVIRT_DEBUG=1
> LIBVIRT_LOG_OUTPUTS=1:stderr /usr/libexec/libvirt_lxc --name testdeb
> --console 17 --security=none --handshake 20 --background --veth veth1
> 2013-03-04 04:17:55.444+0000: 7197: debug : virFileClose:72 : Closed fd 21
> 2013-03-04 04:17:55.444+0000: 7197: debug : virCommandRunAsync:2218 :
> Command result 0, with PID 7294
> 2013-03-04 04:17:55.444+0000: 7294: debug : virFileClose:72 : Closed fd 3
> 2013-03-04 04:17:55.444+0000: 7294: debug : virFileClose:72 : Closed fd 4
> 2013-03-04 04:17:55.444+0000: 7294: debug : virFileClose:72 : Closed fd 5
> 2013-03-04 04:17:55.444+0000: 7294: debug : virFileClose:72 : Closed fd 6
> 2013-03-04 04:17:55.444+0000: 7294: debug : virFileClose:72 : Closed fd 7
> 2013-03-04 04:17:55.444+0000: 7294: debug : virFileClose:72 : Closed fd 8
> 2013-03-04 04:17:55.444+0000: 7294: debug : virFileClose:72 : Closed fd 9
> 2013-03-04 04:17:55.444+0000: 7294: debug : virFileClose:72 : Closed fd 10
> 2013-03-04 04:17:55.444+0000: 7294: debug : virFileClose:72 : Closed fd 11
> 2013-03-04 04:17:55.444+0000: 7294: debug : virFileClose:72 : Closed fd 12
> 2013-03-04 04:17:55.444+0000: 7294: debug : virFileClose:72 : Closed fd 13
> 2013-03-04 04:17:55.444+0000: 7294: debug : virFileClose:72 : Closed fd 14
> 2013-03-04 04:17:55.444+0000: 7294: debug : virFileClose:72 : Closed fd 15
> 2013-03-04 04:17:55.444+0000: 7294: debug : virFileClose:72 : Closed fd 16
> 2013-03-04 04:17:55.444+0000: 7294: debug : virFileClose:72 : Closed fd 19
> 
> That's the last time anything with PID 7294 or lxc appears in the log
> file. I'm unfortunately not getting any lxcContainer debug messages in
> the log using LIBVIRT_DEBUG=1 LIBVIRT_LOG_OUTPUT=1:stderr
> 


Did you check the last version libvirt?
I can't reproduce this problem with last libvirt.

Thanks!
Gao