Arun Sharma
2009-May-28 12:34 UTC
[Xen-users] Xen 3.4 Qcow based Copy of write overlay for Centos base image does not work.
Hello
My requirement is to implement COW by having single base image and multiple
vm having multiple cow files.
For this i have, converted existing tap:aio supported base image of centos
5.2 and tested on xen.
Since qcow2 based Centos52 works fine for me then i tried creating multiple
cow files using qcow-create command. But when i try to run the vm using cow
file it does not work ? Any idea .
Please see below steps which i did.
Assume that i have already working base image which works fine with tap:aio
based driver.
1. Converted to qcow2 format.
qemu-img-xen convert -O qcow2 CentosServer5.2_1.img
CentosServer5.2_1_qcow2.img
where CentosServer5.2_1.img is converted to CentosServer5.2_1_qcow2.img
2. Now creating vm with below xen config. It worked.
disk = [
''tap:qcow2:/var/opt/espresso/centos/CentosServer5.2_1_qcow2.img,xvda,w'',
''tap:aio:/var/opt/espresso/centos/swap.img,xvdb,w''
]
3. Now creating cow file based on above base image.
qcow-create -f qcow2 100M centos.cow CentosServer5.2_1_qcow2.img
4. Trying to create vm now using below xen config. Things fails here.
disk = [
''tap:qcow2:/var/opt/espresso/centos/centos.cow,xvda,w'',
''tap:aio:/var/opt/espresso/centos/swap.img,xvdb,w''
]
# xm create centos.cfg
Using config file "./centos.cfg".
Error: Device 51952 (tap) could not be connected. Setting up the
backend failed. See the log files in /var/log/xen/ for details.
NOT SURE WHAT MISTAKE I AM DOING.
Xend logs are here.
-------------------------------
log/xen/ for details.
Traceback (most recent call last):
File "usr/lib64/python2.4/site-packages/xen/xend/XendDomainInfo.py",
line
3602, in create_vbd
dev_control.waitForDevice(devid)
File
"usr/lib64/python2.4/site-packages/xen/xend/server/DevController.py",
line 164, in waitForDevice
raise VmError("Device %s (%s) could not be connected. "
VmError: Device 51952 (tap) could not be connected. Setting up the backend
failed. See the log files in /var/log/xen/ for details.
[2009-05-28 17:23:27 29552] ERROR (XendDomainInfo:476) VM start failed
Traceback (most recent call last):
File "usr/lib64/python2.4/site-packages/xen/xend/XendDomainInfo.py",
line
456, in start
XendTask.log_progress(31, 60, self._initDomain)
File "usr/lib64/python2.4/site-packages/xen/xend/XendTask.py", line
209,
in log_progress
retval = func(*args, **kwds)
File "usr/lib64/python2.4/site-packages/xen/xend/XendDomainInfo.py",
line
2498, in _initDomain
self._configureBootloader()
File "usr/lib64/python2.4/site-packages/xen/xend/XendDomainInfo.py",
line
2913, in _configureBootloader
dom0._waitForDeviceUUID(dom0.create_vbd(vbd, disk))
File "usr/lib64/python2.4/site-packages/xen/xend/XendDomainInfo.py",
line
3602, in create_vbd
dev_control.waitForDevice(devid)
File
"usr/lib64/python2.4/site-packages/xen/xend/server/DevController.py",
line 164, in waitForDevice
raise VmError("Device %s (%s) could not be connected. "
VmError: Device 51952 (tap) could not be connected. Setting up the backend
failed. See the log files in /var/log/xen/ for details.
[2009-05-28 17:23:27 29552] DEBUG (XendDomainInfo:2723)
XendDomainInfo.destroy: domid=58
[2009-05-28 17:23:27 29552] DEBUG (XendDomainInfo:2203) No device model
[2009-05-28 17:23:27 29552] DEBUG (XendDomainInfo:2205) Releasing devices
[2009-05-28 17:23:27 29552] ERROR (XendDomainInfo:97) Domain construction
failed
Traceback (most recent call last):
File "usr/lib64/python2.4/site-packages/xen/xend/XendDomainInfo.py",
line
95, in create
vm.start()
File "usr/lib64/python2.4/site-packages/xen/xend/XendDomainInfo.py",
line
456, in start
XendTask.log_progress(31, 60, self._initDomain)
File "usr/lib64/python2.4/site-packages/xen/xend/XendTask.py", line
209,
in log_progress
retval = func(*args, **kwds)
File "usr/lib64/python2.4/site-packages/xen/xend/XendDomainInfo.py",
line
2498, in _initDomain
self._configureBootloader()
File "usr/lib64/python2.4/site-packages/xen/xend/XendDomainInfo.py",
line
2913, in _configureBootloader
dom0._waitForDeviceUUID(dom0.create_vbd(vbd, disk))
File "usr/lib64/python2.4/site-packages/xen/xend/XendDomainInfo.py",
line
3602, in create_vbd
dev_control.waitForDevice(devid)
File
"usr/lib64/python2.4/site-packages/xen/xend/server/DevController.py",
line 164, in waitForDevice
raise VmError("Device %s (%s) could not be connected. "
VmError: Device 51952 (tap) could not be connected. Setting up the backend
failed. See the log files in /var/log/xen/ for details.
----------------------------
Any idea ?
Arun
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Arun Sharma
2009-May-28 12:35 UTC
[Xen-users] Re: Xen 3.4 Qcow based Copy of write overlay for Centos base image does not work.
More info My idea is more or less similar to this. http://www.coolacid.net/the-news/152-xen-and-the-art-of-qcows Arun On Thu, May 28, 2009 at 6:04 PM, Arun Sharma <arunain@gmail.com> wrote:> > Hello > > My requirement is to implement COW by having single base image and multiple > vm having multiple cow files. > > For this i have, converted existing tap:aio supported base image of centos > 5.2 and tested on xen. > Since qcow2 based Centos52 works fine for me then i tried creating multiple > cow files using qcow-create command. But when i try to run the vm using cow > file it does not work ? Any idea . > > Please see below steps which i did. > > Assume that i have already working base image which works fine with tap:aio > based driver. > > 1. Converted to qcow2 format. > > qemu-img-xen convert -O qcow2 CentosServer5.2_1.img > CentosServer5.2_1_qcow2.img > > where CentosServer5.2_1.img is converted to > CentosServer5.2_1_qcow2.img > > > 2. Now creating vm with below xen config. It worked. > > disk = [ > ''tap:qcow2:/var/opt/espresso/centos/CentosServer5.2_1_qcow2.img,xvda,w'', > ''tap:aio:/var/opt/espresso/centos/swap.img,xvdb,w'' ] > > 3. Now creating cow file based on above base image. > > qcow-create -f qcow2 100M centos.cow CentosServer5.2_1_qcow2.img > > 4. Trying to create vm now using below xen config. Things fails here. > > disk = [ ''tap:qcow2:/var/opt/espresso/centos/centos.cow,xvda,w'', > ''tap:aio:/var/opt/espresso/centos/swap.img,xvdb,w'' ] > > > # xm create centos.cfg > Using config file "./centos.cfg". > Error: Device 51952 (tap) could not be connected. Setting up > the backend failed. See the log files in /var/log/xen/ for details. > > > NOT SURE WHAT MISTAKE I AM DOING. > > > > Xend logs are here. > ------------------------------- > > log/xen/ for details. > Traceback (most recent call last): > File "usr/lib64/python2.4/site-packages/xen/xend/XendDomainInfo.py", line > 3602, in create_vbd > dev_control.waitForDevice(devid) > File > "usr/lib64/python2.4/site-packages/xen/xend/server/DevController.py", line > 164, in waitForDevice > raise VmError("Device %s (%s) could not be connected. " > VmError: Device 51952 (tap) could not be connected. Setting up the backend > failed. See the log files in /var/log/xen/ for details. > [2009-05-28 17:23:27 29552] ERROR (XendDomainInfo:476) VM start failed > Traceback (most recent call last): > File "usr/lib64/python2.4/site-packages/xen/xend/XendDomainInfo.py", line > 456, in start > XendTask.log_progress(31, 60, self._initDomain) > File "usr/lib64/python2.4/site-packages/xen/xend/XendTask.py", line 209, > in log_progress > retval = func(*args, **kwds) > File "usr/lib64/python2.4/site-packages/xen/xend/XendDomainInfo.py", line > 2498, in _initDomain > self._configureBootloader() > File "usr/lib64/python2.4/site-packages/xen/xend/XendDomainInfo.py", line > 2913, in _configureBootloader > dom0._waitForDeviceUUID(dom0.create_vbd(vbd, disk)) > File "usr/lib64/python2.4/site-packages/xen/xend/XendDomainInfo.py", line > 3602, in create_vbd > dev_control.waitForDevice(devid) > File > "usr/lib64/python2.4/site-packages/xen/xend/server/DevController.py", line > 164, in waitForDevice > raise VmError("Device %s (%s) could not be connected. " > VmError: Device 51952 (tap) could not be connected. Setting up the backend > failed. See the log files in /var/log/xen/ for details. > [2009-05-28 17:23:27 29552] DEBUG (XendDomainInfo:2723) > XendDomainInfo.destroy: domid=58 > [2009-05-28 17:23:27 29552] DEBUG (XendDomainInfo:2203) No device model > [2009-05-28 17:23:27 29552] DEBUG (XendDomainInfo:2205) Releasing devices > [2009-05-28 17:23:27 29552] ERROR (XendDomainInfo:97) Domain construction > failed > Traceback (most recent call last): > File "usr/lib64/python2.4/site-packages/xen/xend/XendDomainInfo.py", line > 95, in create > vm.start() > File "usr/lib64/python2.4/site-packages/xen/xend/XendDomainInfo.py", line > 456, in start > XendTask.log_progress(31, 60, self._initDomain) > File "usr/lib64/python2.4/site-packages/xen/xend/XendTask.py", line 209, > in log_progress > retval = func(*args, **kwds) > File "usr/lib64/python2.4/site-packages/xen/xend/XendDomainInfo.py", line > 2498, in _initDomain > self._configureBootloader() > File "usr/lib64/python2.4/site-packages/xen/xend/XendDomainInfo.py", line > 2913, in _configureBootloader > dom0._waitForDeviceUUID(dom0.create_vbd(vbd, disk)) > File "usr/lib64/python2.4/site-packages/xen/xend/XendDomainInfo.py", line > 3602, in create_vbd > dev_control.waitForDevice(devid) > File > "usr/lib64/python2.4/site-packages/xen/xend/server/DevController.py", line > 164, in waitForDevice > raise VmError("Device %s (%s) could not be connected. " > VmError: Device 51952 (tap) could not be connected. Setting up the backend > failed. See the log files in /var/log/xen/ for details. > > > > > ---------------------------- > > Any idea ? > > Arun > > > > > > > > > > >-- Regards Arun Sharma 0-939-692-3118 _______________________________________________ Xen-users mailing list Xen-users@lists.xensource.com http://lists.xensource.com/xen-users
Fajar A. Nugraha
2009-May-28 17:30 UTC
Re: [Xen-users] Xen 3.4 Qcow based Copy of write overlay for Centos base image does not work.
On Thu, May 28, 2009 at 7:34 PM, Arun Sharma <arunain@gmail.com> wrote:> 3. Now creating cow file based on above base image. > > qcow-create -f qcow2 100M centos.cow CentosServer5.2_1_qcow2.img > > 4. Trying to create vm now using below xen config. Things fails here.Known problem. See https://bugzilla.redhat.com/show_bug.cgi?id=486353 Fix not publicly available yet. -- Fajar _______________________________________________ Xen-users mailing list Xen-users@lists.xensource.com http://lists.xensource.com/xen-users
Arun Sharma
2009-May-29 02:48 UTC
Re: [Xen-users] Xen 3.4 Qcow based Copy of write overlay for Centos base image does not work.
Hello Fajar First of all thanks for your quick reply. After reading the link given by you, i came in below conclusion. 1. Xen 3.4 does not have tap poll on aio support. I have to apply the updated patch and build it again. 2. After patch is implemented , i will be able to run PV HVM guests using qcow overlay. mentioned in my earlier. 3. This patch is already built in RHEL 5.4. (xen-3.0.3-86.el5 ) Is above statements are correct understanding of mine. It will be good if you confirm me. Arun On Thu, May 28, 2009 at 11:00 PM, Fajar A. Nugraha <fajar@fajar.net> wrote:> On Thu, May 28, 2009 at 7:34 PM, Arun Sharma <arunain@gmail.com> wrote: > > 3. Now creating cow file based on above base image. > > > > qcow-create -f qcow2 100M centos.cow > CentosServer5.2_1_qcow2.img > > > > 4. Trying to create vm now using below xen config. Things fails here. > > Known problem. See https://bugzilla.redhat.com/show_bug.cgi?id=486353 > Fix not publicly available yet. > > -- > Fajar >-- Regards Arun Sharma 0-939-692-3118 _______________________________________________ Xen-users mailing list Xen-users@lists.xensource.com http://lists.xensource.com/xen-users
Fajar A. Nugraha
2009-May-29 03:39 UTC
Re: [Xen-users] Xen 3.4 Qcow based Copy of write overlay for Centos base image does not work.
On Fri, May 29, 2009 at 9:48 AM, Arun Sharma <arajmail@gmail.com> wrote:> After reading the link given by you, i came in below conclusion. > > 1. Xen 3.4 does not have tap poll on aio support. I have to apply the > updated patch and build it again.Not exactly. Xen 3.4 seems to have a different problem : http://bugzilla.xensource.com/bugzilla/show_bug.cgi?id=1430> 3. This patch is already built in RHEL 5.4. (xen-3.0.3-86.el5 )Should be. The bottom line is AFAIK both RHEL and Xen 3.4''s implementation of tap:qcow are broken. Perhaps other users can give more info which implementation works. -- Fajar _______________________________________________ Xen-users mailing list Xen-users@lists.xensource.com http://lists.xensource.com/xen-users