On Thu, Nov 12, 2009 at 10:45 AM, Bryn M. Reeves bmr@redhat.com wrote:
On Thu, 2009-11-12 at 09:23 +0000, Mr. Teo En Ming (Zhang Enming) wrote:
Hi All,
I have several Xen virtual machines within logical volumes using LVM2. I did not use disk images for performance reasons.
Conventionally, if I want to clone my virtual machines, I have to dd the LV to an image file. But this consumes a lot of time and harddisk space.
So, instead of doing that, I want to use losetup and kpartx with my logical volumes, which contain operating systems of virtual machines.
I can backup the filesystems of a virtual machine in this way:
# losetup /dev/loop1 /dev/virtualmachines/windows7-x64
What's the point of adding a loopback device on top of the LV? Running kpartx on the LV itself will work just fine and this just adds an unnecessary layer of overhead and complexity unless I am missing something.
dd if=/dev/hda of=mbr.hda bs=512 count=1
Because /dev/hda resides in a logical volume. The logical volume is a virtual harddisk for my virtual machine.
Assuming that the LV given above is a whole-disk image containing a DOS MBR partition table:
dd if=/dev/virtualmachines/windows7-x64 of=/tmp.mbr.img bs=512 count=1
You could also do the same with the loopN device that you set up earlier, although I still don't see the need for that step.
re-create the physical volume (PV)
re-create the volume group
assign the PV to the volume group
restore the LVM metadata, i.e. the configuration files for all the
logical volumes
restore the MBR of my domU
restore the filesystems of my domU
Should work fine, just be sure to test each step so that you are confident and comfortable with it before you find yourself needing to do this in anger.
Regards, Bryn.
-- fedora-list mailing list fedora-list@redhat.com To unsubscribe: https://www.redhat.com/mailman/listinfo/fedora-list Guidelines: http://fedoraproject.org/wiki/Communicate/MailingListGuidelines
Hi Bryn,
I have just tried an experiment without the losetup step. I have verified that it works using kpartx only.
root@sysresccd /root % kpartx -av /dev/virtualmachines/winxphome32 add map virtualmachines-winxphome32p1 (253:22): 0 104840127 linear /dev/virtualmachines/winxphome32 63 root@sysresccd /root % cd /dev/mapper root@sysresccd /dev/mapper % ls *winxphome32* virtualmachines-winxphome32 virtualmachines-winxphome32p1 root@sysresccd /dev/mapper % ls -al *winxphome32* brw-rw---- 1 root disk 253, 0 2009-11-12 15:49 virtualmachines-winxphome32 brw-rw---- 1 root disk 253, 22 2009-11-12 18:47 virtualmachines-winxphome32p1 root@sysresccd /dev/mapper % ls -al *winxphome32* brw-rw---- 1 root disk 253, 0 2009-11-12 15:49 virtualmachines-winxphome32 brw-rw---- 1 root disk 253, 22 2009-11-12 18:47 virtualmachines-winxphome32p1 root@sysresccd /dev/mapper % fdisk -l virtualmachines-winxphome32
Disk virtualmachines-winxphome32: 53.7 GB, 53687091200 bytes 255 heads, 63 sectors/track, 6527 cylinders Units = cylinders of 16065 * 512 = 8225280 bytes Disk identifier: 0x2b362b35
Device Boot Start End Blocks Id System virtualmachines-winxphome32p1 * 1 6526 52420063+ 7 HPFS/NTFS
Without the losetup and the corresponding overhead, it will speed up cloning of my virtual machines within LVs.
On Thu, Nov 12, 2009 at 10:55 AM, Mr. Teo En Ming (Zhang Enming) < space.time.universe@gmail.com> wrote:
On Thu, Nov 12, 2009 at 10:45 AM, Bryn M. Reeves bmr@redhat.com wrote:
On Thu, 2009-11-12 at 09:23 +0000, Mr. Teo En Ming (Zhang Enming) wrote:
Hi All,
I have several Xen virtual machines within logical volumes using LVM2. I did not use disk images for performance reasons.
Conventionally, if I want to clone my virtual machines, I have to dd the LV to an image file. But this consumes a lot of time and harddisk space.
So, instead of doing that, I want to use losetup and kpartx with my logical volumes, which contain operating systems of virtual machines.
I can backup the filesystems of a virtual machine in this way:
# losetup /dev/loop1 /dev/virtualmachines/windows7-x64
What's the point of adding a loopback device on top of the LV? Running kpartx on the LV itself will work just fine and this just adds an unnecessary layer of overhead and complexity unless I am missing something.
dd if=/dev/hda of=mbr.hda bs=512 count=1
Because /dev/hda resides in a logical volume. The logical volume is a virtual harddisk for my virtual machine.
Assuming that the LV given above is a whole-disk image containing a DOS MBR partition table:
dd if=/dev/virtualmachines/windows7-x64 of=/tmp.mbr.img bs=512 count=1
You could also do the same with the loopN device that you set up earlier, although I still don't see the need for that step.
re-create the physical volume (PV)
re-create the volume group
assign the PV to the volume group
restore the LVM metadata, i.e. the configuration files for all the
logical volumes
restore the MBR of my domU
restore the filesystems of my domU
Should work fine, just be sure to test each step so that you are confident and comfortable with it before you find yourself needing to do this in anger.
Regards, Bryn.
-- fedora-list mailing list fedora-list@redhat.com To unsubscribe: https://www.redhat.com/mailman/listinfo/fedora-list Guidelines: http://fedoraproject.org/wiki/Communicate/MailingListGuidelines
Hi Bryn,
I have just tried an experiment without the losetup step. I have verified that it works using kpartx only.
root@sysresccd /root % kpartx -av /dev/virtualmachines/winxphome32 add map virtualmachines-winxphome32p1 (253:22): 0 104840127 linear /dev/virtualmachines/winxphome32 63 root@sysresccd /root % cd /dev/mapper root@sysresccd /dev/mapper % ls *winxphome32* virtualmachines-winxphome32 virtualmachines-winxphome32p1 root@sysresccd /dev/mapper % ls -al *winxphome32* brw-rw---- 1 root disk 253, 0 2009-11-12 15:49 virtualmachines-winxphome32 brw-rw---- 1 root disk 253, 22 2009-11-12 18:47 virtualmachines-winxphome32p1 root@sysresccd /dev/mapper % ls -al *winxphome32* brw-rw---- 1 root disk 253, 0 2009-11-12 15:49 virtualmachines-winxphome32 brw-rw---- 1 root disk 253, 22 2009-11-12 18:47 virtualmachines-winxphome32p1 root@sysresccd /dev/mapper % fdisk -l virtualmachines-winxphome32
Disk virtualmachines-winxphome32: 53.7 GB, 53687091200 bytes 255 heads, 63 sectors/track, 6527 cylinders
Units = cylinders of 16065 * 512 = 8225280 bytes Disk identifier: 0x2b362b35
Device Boot Start End Blocks IdSystem virtualmachines-winxphome32p1 * 1 6526 52420063+ 7 HPFS/NTFS
Without the losetup and the corresponding overhead, it will speed up cloning of my virtual machines within LVs.
-- Mr. Teo En Ming (Zhang Enming) Dip(Mechatronics) BEng(Hons)(Mechanical Engineering) Alma Maters: (1) Singapore Polytechnic (2) National University of Singapore My Primary Blog: http://teo-en-ming-aka-zhang-enming.blogspot.com My Secondary Blog: http://enmingteo.wordpress.com My Youtube videos: http://www.youtube.com/user/enmingteo Email: space.time.universe@gmail.com Mobile Phone (Starhub Prepaid): +65-8369-2618 Street: Bedok Reservoir Road Country: Singapore
Hi All,
I have performed a backup of my F11 Dom0's PV (60 GB) of 3 logical volumes using fsarchiver with the maximum possible LZMA compression. The operation took 4 hours with 2 compression threads. The resulting backup archive size is 8.1 GB for a PV of 60 GB.
My hardware specs:
Intel Pentium Dual Core E6300 2.8 GHz Intel Desktop Board DQ45CB 6 GB DDR2-800 memory
On Thu, Nov 12, 2009 at 12:32 PM, Mr. Teo En Ming (Zhang Enming) < space.time.universe@gmail.com> wrote:
On Thu, Nov 12, 2009 at 10:55 AM, Mr. Teo En Ming (Zhang Enming) < space.time.universe@gmail.com> wrote:
On Thu, Nov 12, 2009 at 10:45 AM, Bryn M. Reeves bmr@redhat.com wrote:
On Thu, 2009-11-12 at 09:23 +0000, Mr. Teo En Ming (Zhang Enming) wrote:
Hi All,
I have several Xen virtual machines within logical volumes using LVM2. I did not use disk images for performance reasons.
Conventionally, if I want to clone my virtual machines, I have to dd the LV to an image file. But this consumes a lot of time and harddisk space.
So, instead of doing that, I want to use losetup and kpartx with my logical volumes, which contain operating systems of virtual machines.
I can backup the filesystems of a virtual machine in this way:
# losetup /dev/loop1 /dev/virtualmachines/windows7-x64
What's the point of adding a loopback device on top of the LV? Running kpartx on the LV itself will work just fine and this just adds an unnecessary layer of overhead and complexity unless I am missing something.
dd if=/dev/hda of=mbr.hda bs=512 count=1
Because /dev/hda resides in a logical volume. The logical volume is a virtual harddisk for my virtual machine.
Assuming that the LV given above is a whole-disk image containing a DOS MBR partition table:
dd if=/dev/virtualmachines/windows7-x64 of=/tmp.mbr.img bs=512 count=1
You could also do the same with the loopN device that you set up earlier, although I still don't see the need for that step.
re-create the physical volume (PV)
re-create the volume group
assign the PV to the volume group
restore the LVM metadata, i.e. the configuration files for all the
logical volumes
restore the MBR of my domU
restore the filesystems of my domU
Should work fine, just be sure to test each step so that you are confident and comfortable with it before you find yourself needing to do this in anger.
Regards, Bryn.
-- fedora-list mailing list fedora-list@redhat.com To unsubscribe: https://www.redhat.com/mailman/listinfo/fedora-list Guidelines: http://fedoraproject.org/wiki/Communicate/MailingListGuidelines
Hi Bryn,
I have just tried an experiment without the losetup step. I have verified that it works using kpartx only.
root@sysresccd /root % kpartx -av /dev/virtualmachines/winxphome32 add map virtualmachines-winxphome32p1 (253:22): 0 104840127 linear /dev/virtualmachines/winxphome32 63 root@sysresccd /root % cd /dev/mapper root@sysresccd /dev/mapper % ls *winxphome32* virtualmachines-winxphome32 virtualmachines-winxphome32p1 root@sysresccd /dev/mapper % ls -al *winxphome32* brw-rw---- 1 root disk 253, 0 2009-11-12 15:49 virtualmachines-winxphome32 brw-rw---- 1 root disk 253, 22 2009-11-12 18:47 virtualmachines-winxphome32p1 root@sysresccd /dev/mapper % ls -al *winxphome32* brw-rw---- 1 root disk 253, 0 2009-11-12 15:49 virtualmachines-winxphome32 brw-rw---- 1 root disk 253, 22 2009-11-12 18:47 virtualmachines-winxphome32p1 root@sysresccd /dev/mapper % fdisk -l virtualmachines-winxphome32
Disk virtualmachines-winxphome32: 53.7 GB, 53687091200 bytes 255 heads, 63 sectors/track, 6527 cylinders
Units = cylinders of 16065 * 512 = 8225280 bytes Disk identifier: 0x2b362b35
Device Boot Start End BlocksId System virtualmachines-winxphome32p1 * 1 6526 52420063+ 7 HPFS/NTFS
Without the losetup and the corresponding overhead, it will speed up cloning of my virtual machines within LVs.
-- Mr. Teo En Ming (Zhang Enming) Dip(Mechatronics) BEng(Hons)(Mechanical Engineering) Alma Maters: (1) Singapore Polytechnic (2) National University of Singapore My Primary Blog: http://teo-en-ming-aka-zhang-enming.blogspot.com My Secondary Blog: http://enmingteo.wordpress.com My Youtube videos: http://www.youtube.com/user/enmingteo Email: space.time.universe@gmail.com Mobile Phone (Starhub Prepaid): +65-8369-2618 Street: Bedok Reservoir Road Country: Singapore
Hi All,
I have performed a backup of my F11 Dom0's PV (60 GB) of 3 logical volumes using fsarchiver with the maximum possible LZMA compression. The operation took 4 hours with 2 compression threads. The resulting backup archive size is 8.1 GB for a PV of 60 GB.
My hardware specs:
Intel Pentium Dual Core E6300 2.8 GHz Intel Desktop Board DQ45CB 6 GB DDR2-800 memory
-- Mr. Teo En Ming (Zhang Enming) Dip(Mechatronics) BEng(Hons)(Mechanical Engineering) Alma Maters: (1) Singapore Polytechnic (2) National University of Singapore My Primary Blog: http://teo-en-ming-aka-zhang-enming.blogspot.com My Secondary Blog: http://enmingteo.wordpress.com My Youtube videos: http://www.youtube.com/user/enmingteo Email: space.time.universe@gmail.com Mobile Phone (Starhub Prepaid): +65-8369-2618 Street: Bedok Reservoir Road Country: Singapore
The fsarchiver command I have used is:
fsarchiver savefs -v -z 9 -j 2 /mnt/hitachi/test/test.fsa /dev/vg_fedora11_host/lv_home /dev/vg_fedora11_host/lv_root /dev/vg_fedora11_host/lv_var
-
Mr. Teo En Ming (Zhang Enming)