Re: How to Backup and Restore MBR within Logical Volumes?
On Fri, Nov 13, 2009 at 1:25 PM, Mr. Teo En Ming (Zhang Enming) space.time.unive...@gmail.com wrote: On Fri, Nov 13, 2009 at 11:17 AM, Mr. Teo En Ming (Zhang Enming) space.time.unive...@gmail.com wrote: On Fri, Nov 13, 2009 at 5:40 AM, Sergey Vlasov v...@altlinux.ru wrote: On Fri, Nov 13, 2009 at 12:57:22AM +0800, Mr. Teo En Ming (Zhang Enming) wrote: [...] # VM 11: Rocks 5.1 x86_64 HPC Compute Cluster HVM domU kpartx -av /dev/virtualmachines/rocks0001 dd if=/dev/virtualmachines/rocks0001 of=$DEST/rocks0001.mbr bs=512 count=1 partimage -d -M -b -z1 save /dev/mapper/virtualmachines-rocks0001p1 $DEST/virtualmachines-rocks0001p1.img partimage -d -M -b -z1 save /dev/mapper/virtualmachines-rocks0001p2 $DEST/virtualmachines-rocks0001p2.img partimage -d -M -b -z1 save /dev/mapper/virtualmachines-rocks0001p5 $DEST/virtualmachines-rocks0001p5.img Note that this VM (and some other VMs listed in your script) uses logical partitions. In this case just saving a copy of MBR will not be enough to save partition layout - MBR describes only 4 primary partitions, and restoring just MBR will not restore extended partitions. One way to backup the complete partition layout is by saving also the output of sfdisk -d $device; the resulting file can be used as input to sfdisk to restore all partitions, including logical ones. Saving MBR is still needed together with sfdisk, because it saves the boot code (used for HVM) and CHS geometry information (which can be used during boot in some cases). -BEGIN PGP SIGNATURE- Version: GnuPG v1.4.10 (GNU/Linux) iEYEARECAAYFAkr8gM8ACgkQW82GfkQfsqLa+QCaAqpO5NWhYHtKVi3M5ytERw27 eC0AnjsJuG34MAR1jZRejBiJCVybQvc1 =RRGH -END PGP SIGNATURE- ___ Xen-users mailing list xen-us...@lists.xensource.com http://lists.xensource.com/xen-users Thank you for pointing this out. Otherwise I would made incomplete backups. Would it be best practice to always backup both the MBR and the partition geometry using sfdisk whenever cloning our harddisks on desktops and servers? Besides sfdisk, there are also other partitioning tools like fdisk, cfdisk, and parted. Could these other tools also be used for backing up the partition geometry like sfdisk? Thank you. -- 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.unive...@gmail.com Mobile Phone (Starhub Prepaid): +65-8369-2618 Street: Bedok Reservoir Road Country: Singapore Hi, I have made some improvements to the backup/cloning script. Please help me to vet it through for any mistakes. Thank you very much! SCRIPT ---SNIPPED--- /SCRIPT -- 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.unive...@gmail.com Mobile Phone (Starhub Prepaid): +65-8369-2618 Street: Bedok Reservoir Road Country: Singapore Hi All, This is the final version of my backup script. I have gone through the script once to make sure there are no mistakes. If I want to capture any errors during the execution of the backup/cloning script, which of the following commands do I run? # ./backup-script.sh backup.log OR # ./backup-script.sh 2 backup.log After completing the backup script, I will proceed to write the restore script. If there are any errors, please let me know because I do not want to make any mistakes with the cloning process. Thank you. SCRIPT #!/bin/sh ### ### # Script to Backup/Clone Xen Host/Dom0 and all DomUs which are using Logical Volumes as Virtual Hard Disks ### ### # Written by: # Mr. Teo En Ming (Zhang Enming) Dip(Mechatronics) BEng(Hons)(Mechanical Engineering) # Alma Maters: # (1) Singapore Polytechnic # (2) National University of Singapore # Primary Blog: http://teo-en-ming-aka-zhang-enming.blogspot.com # Secondary Blog: http://enmingteo.wordpress.com # Youtube Videos: http://www.youtube.com/user/enmingteo # Xen Tutorials and Video Demos:
Re: Re: How to Backup and Restore MBR within Logical Volumes?
On Fri, Nov 13, 2009 at 5:35 PM, Mr. Teo En Ming (Zhang Enming) space.time.unive...@gmail.com wrote: On Fri, Nov 13, 2009 at 1:25 PM, Mr. Teo En Ming (Zhang Enming) space.time.unive...@gmail.com wrote: On Fri, Nov 13, 2009 at 11:17 AM, Mr. Teo En Ming (Zhang Enming) space.time.unive...@gmail.com wrote: On Fri, Nov 13, 2009 at 5:40 AM, Sergey Vlasov v...@altlinux.ru wrote: On Fri, Nov 13, 2009 at 12:57:22AM +0800, Mr. Teo En Ming (Zhang Enming) wrote: [...] # VM 11: Rocks 5.1 x86_64 HPC Compute Cluster HVM domU kpartx -av /dev/virtualmachines/rocks0001 dd if=/dev/virtualmachines/rocks0001 of=$DEST/rocks0001.mbr bs=512 count=1 partimage -d -M -b -z1 save /dev/mapper/virtualmachines-rocks0001p1 $DEST/virtualmachines-rocks0001p1.img partimage -d -M -b -z1 save /dev/mapper/virtualmachines-rocks0001p2 $DEST/virtualmachines-rocks0001p2.img partimage -d -M -b -z1 save /dev/mapper/virtualmachines-rocks0001p5 $DEST/virtualmachines-rocks0001p5.img Note that this VM (and some other VMs listed in your script) uses logical partitions. In this case just saving a copy of MBR will not be enough to save partition layout - MBR describes only 4 primary partitions, and restoring just MBR will not restore extended partitions. One way to backup the complete partition layout is by saving also the output of sfdisk -d $device; the resulting file can be used as input to sfdisk to restore all partitions, including logical ones. Saving MBR is still needed together with sfdisk, because it saves the boot code (used for HVM) and CHS geometry information (which can be used during boot in some cases). -BEGIN PGP SIGNATURE- Version: GnuPG v1.4.10 (GNU/Linux) iEYEARECAAYFAkr8gM8ACgkQW82GfkQfsqLa+QCaAqpO5NWhYHtKVi3M5ytERw27 eC0AnjsJuG34MAR1jZRejBiJCVybQvc1 =RRGH -END PGP SIGNATURE- ___ Xen-users mailing list xen-us...@lists.xensource.com http://lists.xensource.com/xen-users Thank you for pointing this out. Otherwise I would made incomplete backups. Would it be best practice to always backup both the MBR and the partition geometry using sfdisk whenever cloning our harddisks on desktops and servers? Besides sfdisk, there are also other partitioning tools like fdisk, cfdisk, and parted. Could these other tools also be used for backing up the partition geometry like sfdisk? Thank you. -- 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.unive...@gmail.com Mobile Phone (Starhub Prepaid): +65-8369-2618 Street: Bedok Reservoir Road Country: Singapore Hi, I have made some improvements to the backup/cloning script. Please help me to vet it through for any mistakes. Thank you very much! SCRIPT ***SNIPPED*** /SCRIPT -- 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.unive...@gmail.com Mobile Phone (Starhub Prepaid): +65-8369-2618 Street: Bedok Reservoir Road Country: Singapore Hi All, This is the final version of my backup script. I have gone through the script once to make sure there are no mistakes. If I want to capture any errors during the execution of the backup/cloning script, which of the following commands do I run? # ./backup-script.sh backup.log OR # ./backup-script.sh 2 backup.log After completing the backup script, I will proceed to write the restore script. If there are any errors, please let me know because I do not want to make any mistakes with the cloning process. Thank you. SCRIPT ***SNIPPED*** /SCRIPT -- 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.unive...@gmail.com Mobile Phone (Starhub Prepaid): +65-8369-2618 Street: Bedok Reservoir Road Country: Singapore Dear All, This is the *initial* version of my data restore script. SCRIPT #!/bin/sh ### ### # Script to Restore Xen Host/Dom0
Re: Re: How to Backup and Restore MBR within Logical Volumes?
On Fri, Nov 13, 2009 at 9:17 PM, Dustin Henning dustin.henn...@prd-inc.comwrote: As you are running Windows, I will assume that you are using HVM, and therefore that /dev/virtualmachines/windows7-x64 is a hard disk image. As such, the command you listed will back up the MBR, including the partition table. That isn't to say that Windows 7 doesn't have additional boot information outside of the MBR, but that information would be included in a file system backup. Wikipedia has the structure of the MBR in a table at http://en.wikipedia.org/wiki/Master_boot_record. On that note, I often use bs=446 when I want the MBR without the partition table, but if you are backing up the partition as opposed to the file structure, then you might as well keep the partition table (or even just back up the image). Dustin From: fedora-xen-boun...@redhat.com [mailto:fedora-xen-boun...@redhat.com] On Behalf Of Mr. Teo En Ming (Zhang Enming) Sent: Thursday, November 12, 2009 04:45 To: Geert Janssens Cc: Community assistance, encouragement, and advice for using Fedora.; xen-us...@lists.xensource.com; Fedora Xen Subject: [Fedora-xen] Re: [Xen-users] How to Backup and Restore MBR within Logical Volumes? dd if=/dev/virtualmachines/windows7-x64 of=mbr.w7-x64 bs=512 count=1 I think if you do this, you are only backing up the first 512 bytes of the logical volume, not the MBR. Someone correct me if I am wrong. -- 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.unive...@gmail.com Mobile Phone (Starhub Prepaid): +65-8369-2618 Street: Bedok Reservoir Road Country: Singapore On Thu, Nov 12, 2009 at 9:36 AM, Geert Janssens i...@kobaltwit.be wrote: On Thursday 12 November 2009, 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 Are you sure you need to call losetup first ? I remember I used kpartx directly on the lvm containing my vbd. Also, I think you can treat the lvm based vbd as a real disk. So dd if=/dev/virtualmachines/windows7-x64 of=mbr.w7-x64 bs=512 count=1 should backup your mbr. Anyone correct me if I'm wrong please. Geert -- Kobalt W.I.T. Web Information Technology Brusselsesteenweg 152 1850 Grimbergen Tel : +32 479 339 655 Email: i...@kobaltwit.be ___ Xen-users mailing list xen-us...@lists.xensource.com http://lists.xensource.com/xen-users Hi Dustin, The MBR backup guide that I was following is this one: Article: MBR tricks with LinuxLink: http://www.tuxation.com/mbr-tricks-with-linux.htmlHere is the final version of my data restore script. Could you check if there are mistakes in it? SCRIPT #!/bin/sh ### ### # Script to Restore Xen Host/Dom0 and all DomUs which are using Logical Volumes as Virtual Hard Disks ### ### # Written by: # Mr. Teo En Ming (Zhang Enming) Dip(Mechatronics) BEng(Hons)(Mechanical Engineering) # Alma Maters: # (1) Singapore Polytechnic # (2) National University of Singapore # Primary Blog: http://teo-en-ming-aka-zhang-enming.blogspot.com # Secondary Blog: http://enmingteo.wordpress.com # Youtube Videos: http://www.youtube.com/user/enmingteo # Xen Tutorials and Video Demos: http://www.xen.org/support/tutorial.html # Email: space.time.unive...@gmail.com # MSN: teoenm...@hotmail.com # Mobile Phone (Starhub Prepaid): +65-8369-2618 # Street: Bedok Reservoir Road # Country: Singapore # First written: 13 November 2009 Friday 6:49 P.M. Singapore time # Last updated: 13 November 2009 Friday 8:25 P.M. Singapore time # Last updated: 13 November 2009 Friday 8:59 P.M. Singapore time # Last updated: 13 November 2009 Friday 9:40 P.M. Singapore time # REFERNCE: Geek Sheet: Bare-metal backup and recovery, May 7th
How to Backup and Restore MBR within Logical Volumes?
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 virtualmachines is the name of my volume group. windows7-x64 is the logical volume. # kpartx -av /dev/loop1 Then I would see the partitions of the virtual machine within a logical volume, like so: /dev/mapper/loop1p1 /dev/mapper/loop1p2 /dev/mapper/loop1p3 Now that I can access the partitions of the virtual machine within a logical volume, I can use partimage or fsarchiver to backup the partitions (provided the filesystem is supported by the archiver). But the problem is that I can only backup/clone the filesystems of my virtual machine within a logical volume. I can't backup the Master Boot Record (MBR) of the virtual machine within a logical volume. For example, 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. I would like to know how to backup and also restore the MBR of my virtual machine/guest operating system/domU within a logical volume because the losetup and kpartx procedure only allows me access to the partitions, not the MBR. A complete backup of a virtual machine (and also a bare metal machine) includes the MBR and all filesystems. If there is a catastrophic failure with my logical volumes containing domUs, I would like to 1) re-create the physical volume (PV) 2) re-create the volume group 3) assign the PV to the volume group 4) restore the LVM metadata, i.e. the configuration files for all the logical volumes 5) restore the MBR of my domU 6) restore the filesystems of my domU Please advise. Thank you very much. -- 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.unive...@gmail.com Mobile Phone (Starhub Prepaid): +65-8369-2618 Street: Bedok Reservoir Road Country: Singapore -- 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
Re: How to Backup and Restore MBR within Logical Volumes?
Mr. Teo En Ming (Zhang Enming) wrote: # kpartx -av /dev/loop1 [...] But the problem is that I can only backup/clone the filesystems of my virtual machine within a logical volume. I can't backup the Master Boot Record (MBR) of the virtual machine within a logical volume. For example, 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. Maybe I didn't really understand your setup, but... isn't your mbr simply on /dev/loop1? -- Roberto Ragusamail at robertoragusa.it -- 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
Re: [Xen-users] How to Backup and Restore MBR within Logical Volumes?
dd if=/dev/virtualmachines/windows7-x64 of=mbr.w7-x64 bs=512 count=1 I think if you do this, you are only backing up the first 512 bytes of the logical volume, not the MBR. Someone correct me if I am wrong. -- 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.unive...@gmail.com Mobile Phone (Starhub Prepaid): +65-8369-2618 Street: Bedok Reservoir Road Country: Singapore On Thu, Nov 12, 2009 at 9:36 AM, Geert Janssens i...@kobaltwit.be wrote: On Thursday 12 November 2009, 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 Are you sure you need to call losetup first ? I remember I used kpartx directly on the lvm containing my vbd. Also, I think you can treat the lvm based vbd as a real disk. So dd if=/dev/virtualmachines/windows7-x64 of=mbr.w7-x64 bs=512 count=1 should backup your mbr. Anyone correct me if I'm wrong please. Geert -- Kobalt W.I.T. Web Information Technology Brusselsesteenweg 152 1850 Grimbergen Tel : +32 479 339 655 Email: i...@kobaltwit.be ___ Xen-users mailing list xen-us...@lists.xensource.com http://lists.xensource.com/xen-users -- 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
Re: How to Backup and Restore MBR within Logical Volumes?
Maybe I didn't really understand your setup, but... isn't your mbr simply on /dev/loop1? Yes, you are right. r...@sysresccd /mnt/hitachi/test % fdisk -l /dev/loop1 Disk /dev/loop1: 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 /dev/loop1p1 * 1652652420063+ 7 HPFS/NTFS I am so used with device nomenclature of harddisks being /dev/hda, /dev/hdb, /dev/sda, /dev/md0, /dev/xvda, etc that it didn't occur to me that the device node of my virtual machine in a logical volume is very simply /dev/loop1 after I have performed the losetup /dev/loop1 /dev/volumegroup/logicalvolume step. Thank you very much for enlightening me! Now I can proceed with writing the backup and restore script for my Fedora 11 Dom0 (all partitions using LVM2 logical volumes) and all of my Xen virtual machines (contained in logical volumes). -- 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.unive...@gmail.com Mobile Phone (Starhub Prepaid): +65-8369-2618 Street: Bedok Reservoir Road Country: Singapore On Thu, Nov 12, 2009 at 9:38 AM, Roberto Ragusa m...@robertoragusa.itwrote: Mr. Teo En Ming (Zhang Enming) wrote: # kpartx -av /dev/loop1 [...] But the problem is that I can only backup/clone the filesystems of my virtual machine within a logical volume. I can't backup the Master Boot Record (MBR) of the virtual machine within a logical volume. For example, 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. Maybe I didn't really understand your setup, but... isn't your mbr simply on /dev/loop1? -- Roberto Ragusamail at robertoragusa.it -- 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 -- 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
Re: [Fedora-xen] How to Backup and Restore MBR within Logical Volumes?
Thank you for your advice! Is it called LVM snapshot? -- 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.unive...@gmail.com Mobile Phone (Starhub Prepaid): +65-8369-2618 Street: Bedok Reservoir Road Country: Singapore 2009/11/12 Veli-Pekka Kestilä fed...@guagua.fi 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. # losetup /dev/loop1 /dev/virtualmachines/windows7-x64 windows7-x64 is the logical volume. # kpartx -av /dev/loop1 Then I would see the partitions of the virtual machine within a logical volume, like so: /dev/mapper/loop1p1 /dev/mapper/loop1p2 /dev/mapper/loop1p3 Now that I can access the partitions of the virtual machine within a logical volume, I can use partimage or fsarchiver to backup the partitions (provided the filesystem is supported by the archiver). But the problem is that I can only backup/clone the filesystems of my virtual machine within a logical volume. I can't backup the Master Boot Record (MBR) of the virtual machine within a logical volume. For example, 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. You can do dd if=/dev/dev/loop1 of=mbr.dha bs=512 count=1 to make the copy of the boot block. I would like to know how to backup and also restore the MBR of my virtual machine/guest operating system/domU within a logical volume because the losetup and kpartx procedure only allows me access to the partitions, not the MBR. A complete backup of a virtual machine (and also a bare metal machine) includes the MBR and all filesystems. If there is a catastrophic failure with my logical volumes containing domUs, I would like to 1) re-create the physical volume (PV) 2) re-create the volume group 3) assign the PV to the volume group 4) restore the LVM metadata, i.e. the configuration files for all the logical volumes 5) restore the MBR of my domU 6) restore the filesystems of my domU Of these steps you can recreate 1,2,3 and 4 just by keeping records of their parameters and using normal fdisk, pvcreate, vgcreate and lvcreate commands. For the things inside of lvm you can use losetup to make the loopback device out of the lv where you want to install the quest operating system and then recreate mbr from the file. Problem probably is how to recreate the filesystems if your backup software cannot do it. Also with windows protected system files can be a problem if backup software doesn't support them. One thing you could of course do is to make the system restore backup inside of the DomU when it's running. And then boot new DomU when starting up and use the system backup to restore. (of course this is still more work that pure dd from one place to another.) Problem is that everything else than using dd can have it fair share of problems. If the domU can't be offline too long, you could allocate more space and use the lvm:s instant cloning features (can't remember the name just now. ) and then use dd with gzip or bzip to make the backup from this clone to keep the space requirements minimum for the stored copies. And have minimum disruption for the DomU. -vpk -- Fedora-xen mailing list fedora-...@redhat.com https://www.redhat.com/mailman/listinfo/fedora-xen -- 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
Re: [Xen-users] Re: How to Backup and Restore MBR within Logical Volumes?
Hi, I don't think I will be using the LVM snapshot method. I will simply ensure that my domU is not running, then I proceed to do the losetup and kpartx procedure. Subsequently I will backup the MBR of my domU by dd-ing /dev/loopX and clone all the filesystems of the domU using fsarchiver. I would like to use fsarchiver because it can support LZMA compression. LZMA can compress better than bzip2 and decompress 3x faster than bzip2. partimage only supports gzip and bzip2. -- 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.unive...@gmail.com Mobile Phone (Starhub Prepaid): +65-8369-2618 Street: Bedok Reservoir Road Country: Singapore On Thu, Nov 12, 2009 at 10:02 AM, Fajar A. Nugraha fa...@fajar.net wrote: On Thu, Nov 12, 2009 at 4:52 PM, Mr. Teo En Ming (Zhang Enming) space.time.unive...@gmail.com wrote: Now I can proceed with writing the backup and restore script for my Fedora 11 Dom0 (all partitions using LVM2 logical volumes) and all of my Xen virtual machines (contained in logical volumes). A reminder though: don't forget to create a consistent, unchanging version of domU storage before doing backup. Either by shutting down domU, or by creating LVM snapshot first. Also, if it comes to Windows domUs, I find ntfsclone is better than fsarchiver. One of the reasons is that fsarchiver can not create compressed files during restore. -- Fajar -- 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
Re: How to Backup and Restore MBR within Logical Volumes?
On Thu, 2009-11-12 at 09:23 +, 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. 1) re-create the physical volume (PV) 2) re-create the volume group 3) assign the PV to the volume group 4) restore the LVM metadata, i.e. the configuration files for all the logical volumes 5) restore the MBR of my domU 6) 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
Re: [Xen-users] How to Backup and Restore MBR within Logical Volumes?
On Thu, 2009-11-12 at 09:45 +, Mr. Teo En Ming (Zhang Enming) wrote:
dd if=/dev/virtualmachines/windows7-x64 of=mbr.w7-x64 bs=512 count=1
I think if you do this, you are only backing up the first 512 bytes of
the logical volume, not the MBR.
Someone correct me if I am wrong.
That *is* the MBR (it's the 0th sector of the disk image).
Take a look at the sector on the device (or an image of it) with e.g.
file or a hexdump tool:
[...@hex ~]$ sudo dd if=/dev/mapper/vg_hex-lv_win7 bs=512 count=1 | file
-
1+0 records in
1+0 records out
512 bytes (512 B) copied, 0.0184184 s, 27.8 kB/s
/dev/stdin: x86 boot sector; partition 1: ID=0x7, active, starthead 1,
startsector 63, 125821017 sectors, code offset 0xc0, OEM-ID м,
Bytes/sector 190, sectors/cluster 124, reserved sectors 191, FATs 6,
root entries 185, sectors 64514 (volumes =32 MB) , Media descriptor
0xf3, sectors/FAT 20644, heads 6, hidden sectors 309755, sectors
2147991229 (volumes 32 MB) , physical drive 0x7e, dos 4.0 BootSector
(0x0)
[...@hex ~]$ sudo dd if=/dev/mapper/vg_hex-lv_win7 bs=512 count=1 | xxd
1+0 records in
1+0 records out
512 bytes (512 B) copied, 0.00285548 s, 179 kB/s
000: 33c0 8ed0 bc00 7c8e c08e d8be 007c bf00 3.|..|..
010: 06b9 0002 fcf3 a450 681c 06cb fbb9 0400 ...Ph...
020: bdbe 0780 7e00 007c 0b0f 850e 0183 c510 ~..|
030: e2f1 cd18 8856 0055 c646 1105 c646 1000 .V.U.F...F..
040: b441 bbaa 55cd 135d 720f 81fb 55aa 7509 .A..U..]r...U.u.
050: f7c1 0100 7403 fe46 1066 6080 7e10 0074 t..F.f`.~..t
060: 2666 6800 0066 ff76 0868 6800 fhf.v.h..h.
070: 7c68 0100 6810 00b4 428a 5600 8bf4 cd13 |h..h...B.V.
080: 9f83 c410 9eeb 14b8 0102 bb00 7c8a 5600 |.V.
090: 8a76 018a 4e02 8a6e 03cd 1366 6173 1cfe .v..N..n...fas..
0a0: 4e11 750c 807e 0080 0f84 8a00 b280 eb84 N.u..~..
0b0: 5532 e48a 5600 cd13 5deb 9e81 3efe 7d55 U2..V...]}U
0c0: aa75 6eff 7600 e88d 0075 17fa b0d1 e664 .un.vu.d
0d0: e883 00b0 dfe6 60e8 7c00 b0ff e664 e875 ..`.|d.u
0e0: 00fb b800 bbcd 1a66 23c0 753b 6681 fb54 ...f#.u;f..T
0f0: 4350 4175 3281 f902 0172 2c66 6807 bb00 CPAu2r,fh...
100: 0066 6800 0200 0066 6808 0066 5366 .fhfhfSf
110: 5366 5566 6800 0066 6800 7c00 0066 SfUfhfh.|..f
120: 6168 07cd 1a5a 32f6 ea00 7c00 00cd ah.Z2...|...
130: 18a0 b707 eb08 a0b6 07eb 03a0 b507 32e4 ..2.
140: 0500 078b f0ac 3c00 7409 bb07 00b4 0ecd ...t...
150: 10eb f2f4 ebfd 2bc9 e464 eb00 2402 e0f8 ..+..d..$...
160: 2402 c349 6e76 616c 6964 2070 6172 7469 $..Invalid parti
170: 7469 6f6e 2074 6162 6c65 0045 7272 6f72 tion table.Error
180: 206c 6f61 6469 6e67 206f 7065 7261 7469 loading operati
190: 6e67 2073 7973 7465 6d00 4d69 7373 696e ng system.Missin
1a0: 6720 6f70 6572 6174 696e 6720 7379 7374 g operating syst
1b0: 656d 0063 7b9a 998c 3463 8001 em...c{...4c
1c0: 0100 07fe 3f00 59e0 7f07 ..?...Y.
1d0:
1e0:
1f0: 55aa ..U.
Regards,
Bryn.
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Re: How to Backup and Restore MBR within Logical Volumes?
On Thu, Nov 12, 2009 at 10:45 AM, Bryn M. Reeves b...@redhat.com wrote: On Thu, 2009-11-12 at 09:23 +, 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. 1) re-create the physical volume (PV) 2) re-create the volume group 3) assign the PV to the volume group 4) restore the LVM metadata, i.e. the configuration files for all the logical volumes 5) restore the MBR of my domU 6) 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. r...@sysresccd /root % kpartx -av /dev/virtualmachines/winxphome32 add map virtualmachines-winxphome32p1 (253:22): 0 104840127 linear /dev/virtualmachines/winxphome32 63 r...@sysresccd /root % cd /dev/mapper r...@sysresccd /dev/mapper % ls *winxphome32* virtualmachines-winxphome32 virtualmachines-winxphome32p1 r...@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 r...@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 r...@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 * 1652652420063+ 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.unive...@gmail.com Mobile Phone (Starhub Prepaid): +65-8369-2618 Street: Bedok Reservoir Road Country: Singapore -- 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
Re: How to Backup and Restore MBR within Logical Volumes?
On Thu, Nov 12, 2009 at 10:55 AM, Mr. Teo En Ming (Zhang Enming) space.time.unive...@gmail.com wrote: On Thu, Nov 12, 2009 at 10:45 AM, Bryn M. Reeves b...@redhat.com wrote: On Thu, 2009-11-12 at 09:23 +, 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. 1) re-create the physical volume (PV) 2) re-create the volume group 3) assign the PV to the volume group 4) restore the LVM metadata, i.e. the configuration files for all the logical volumes 5) restore the MBR of my domU 6) 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. r...@sysresccd /root % kpartx -av /dev/virtualmachines/winxphome32 add map virtualmachines-winxphome32p1 (253:22): 0 104840127 linear /dev/virtualmachines/winxphome32 63 r...@sysresccd /root % cd /dev/mapper r...@sysresccd /dev/mapper % ls *winxphome32* virtualmachines-winxphome32 virtualmachines-winxphome32p1 r...@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 r...@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 r...@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 * 1652652420063+ 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.unive...@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.unive...@gmail.com Mobile Phone (Starhub Prepaid): +65-8369-2618 Street: Bedok Reservoir Road Country: Singapore -- fedora-list mailing list fedora-list@redhat.com To unsubscribe: https://www.redhat.com/mailman/listinfo/fedora-list
Re: How to Backup and Restore MBR within Logical Volumes?
On Thu, Nov 12, 2009 at 12:32 PM, Mr. Teo En Ming (Zhang Enming) space.time.unive...@gmail.com wrote: On Thu, Nov 12, 2009 at 10:55 AM, Mr. Teo En Ming (Zhang Enming) space.time.unive...@gmail.com wrote: On Thu, Nov 12, 2009 at 10:45 AM, Bryn M. Reeves b...@redhat.com wrote: On Thu, 2009-11-12 at 09:23 +, 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. 1) re-create the physical volume (PV) 2) re-create the volume group 3) assign the PV to the volume group 4) restore the LVM metadata, i.e. the configuration files for all the logical volumes 5) restore the MBR of my domU 6) 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. r...@sysresccd /root % kpartx -av /dev/virtualmachines/winxphome32 add map virtualmachines-winxphome32p1 (253:22): 0 104840127 linear /dev/virtualmachines/winxphome32 63 r...@sysresccd /root % cd /dev/mapper r...@sysresccd /dev/mapper % ls *winxphome32* virtualmachines-winxphome32 virtualmachines-winxphome32p1 r...@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 r...@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 r...@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 * 1652652420063+ 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.unive...@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.unive...@gmail.com Mobile Phone (Starhub Prepaid): +65-8369-2618 Street: Bedok Reservoir Road Country:
Re: [Xen-users] How to Backup and Restore MBR within Logical Volumes?
On Thu, Nov 12, 2009 at 6:18 PM, Geert Janssens i...@kobaltwit.be wrote: On Thursday 12 November 2009, you wrote: dd if=/dev/virtualmachines/windows7-x64 of=mbr.w7-x64 bs=512 count=1 I think if you do this, you are only backing up the first 512 bytes of the logical volume, not the MBR. Someone correct me if I am wrong. I did some tests just to be sure. As far as I can tell, dd interacts with lvm in exactly the same way as with a physical disk or a loop device. In the test I copied the first sector directly from the lvm partition or via the loop device. It results in exactly the same sector being copied. Also, if you try fdisk -l on the lvm disk or the loop device, it results in the same output. Below is the output from my tests: [r...@aragorn:~]# losetup /dev/loop1 /dev/base/kobaltwit_f11_disk [r...@aragorn:~]# fdisk -l /dev/base/kobaltwit_f11_disk Disk /dev/base/kobaltwit_f11_disk: 10.7 GB, 10737418240 bytes 255 heads, 63 sectors/track, 1305 cylinders Units = cylinders of 16065 * 512 = 8225280 bytes Device Boot Start End Blocks Id System /dev/base/kobaltwit_f11_disk1 * 1130510482381 83 Linux [r...@aragorn:~]# fdisk -l /dev/base/kobaltwit_f11_disk Disk /dev/base/kobaltwit_f11_disk: 10.7 GB, 10737418240 bytes 255 heads, 63 sectors/track, 1305 cylinders Units = cylinders of 16065 * 512 = 8225280 bytes Device Boot Start End Blocks Id System /dev/base/kobaltwit_f11_disk1 * 1130510482381 83 Linux [r...@aragorn:~]# dd if=/dev/base/kobaltwit_f11_disk of=mbr.lvm bs=512 count=1 1+0 records in 1+0 records out 512 bytes (512 B) copied, 7.6e-05 seconds, 6.7 MB/s [r...@aragorn:~]# dd if=/dev/loop1 of=mbr.loop bs=512 count=1 1+0 records in 1+0 records out 512 bytes (512 B) copied, 0.000151 seconds, 3.4 MB/s [r...@aragorn:~]# diff mbr.l* [r...@aragorn:~]# These test seem to indicate to me that the lvm layer in completely transparent to userland tools such as fdisk or dd. So I still think the losetup step is superfluous and possibly causing unnecessary overhead. Geert -- Kobalt W.I.T. Web Information Technology Brusselsesteenweg 152 1850 Grimbergen Tel : +32 479 339 655 Email: i...@kobaltwit.be Thank you! I will omit the losetup step. -- 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.unive...@gmail.com Mobile Phone (Starhub Prepaid): +65-8369-2618 Street: Bedok Reservoir Road Country: Singapore -- 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
Re: [Xen-users] Re: How to Backup and Restore MBR within Logical Volumes?
On Thu, Nov 12, 2009 at 6:37 PM, Fajar A. Nugraha fa...@fajar.net wrote: On Thu, Nov 12, 2009 at 5:10 PM, Mr. Teo En Ming (Zhang Enming) space.time.unive...@gmail.com wrote: Hi, I don't think I will be using the LVM snapshot method. I will simply ensure that my domU is not running, Ah, so you can live with the down time. It makes things a lot simpler then. then I proceed to do the losetup and kpartx procedure. Like others mentioned, you don't need losetup for LVs. It will only make things slower. Subsequently I will backup the MBR of my domU by dd-ing /dev/loopX and clone all the filesystems of the domU using fsarchiver. I would like to use fsarchiver because it can support LZMA compression. LZMA can compress better than bzip2 and decompress 3x faster than bzip2. partimage only supports gzip and bzip2. If your concern is the size and speed of backup, here's one final note from me: you might want to look at zfs. Possible use scenarios : - use opensolaris as dom0. Probably the most supported option when it comes to xen + zfs, but you need to be familiar with how opensolaris works. - use external storage server running solaris/opensolaris as iscsi SAN. Think of it as poor-man's Netapp. - use zfs-fuse inside Linux dom0, and store domU storage as files - use zfs-fuse on domU, and do backup from domU instead of dom0. With zfs, you'd get zfs snapshot (which is like instaneous in-place backup), incremental block-level send (can greatly reduce backup storage size if your data doesn't change often), optional transparent compression for live data (like what ntfs has). -- Fajar I am not familiar with OpenSolaris but that may change with time. -- 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.unive...@gmail.com Mobile Phone (Starhub Prepaid): +65-8369-2618 Street: Bedok Reservoir Road Country: Singapore -- 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
Re: [Xen-users] Re: How to Backup and Restore MBR within Logical Volumes?
On Thu, Nov 12, 2009 at 8:53 PM, Mr. Teo En Ming (Zhang Enming) space.time.unive...@gmail.com wrote: On Thu, Nov 12, 2009 at 6:37 PM, Fajar A. Nugraha fa...@fajar.net wrote: On Thu, Nov 12, 2009 at 5:10 PM, Mr. Teo En Ming (Zhang Enming) space.time.unive...@gmail.com wrote: Hi, I don't think I will be using the LVM snapshot method. I will simply ensure that my domU is not running, Ah, so you can live with the down time. It makes things a lot simpler then. then I proceed to do the losetup and kpartx procedure. Like others mentioned, you don't need losetup for LVs. It will only make things slower. Subsequently I will backup the MBR of my domU by dd-ing /dev/loopX and clone all the filesystems of the domU using fsarchiver. I would like to use fsarchiver because it can support LZMA compression. LZMA can compress better than bzip2 and decompress 3x faster than bzip2. partimage only supports gzip and bzip2. If your concern is the size and speed of backup, here's one final note from me: you might want to look at zfs. Possible use scenarios : - use opensolaris as dom0. Probably the most supported option when it comes to xen + zfs, but you need to be familiar with how opensolaris works. - use external storage server running solaris/opensolaris as iscsi SAN. Think of it as poor-man's Netapp. - use zfs-fuse inside Linux dom0, and store domU storage as files - use zfs-fuse on domU, and do backup from domU instead of dom0. With zfs, you'd get zfs snapshot (which is like instaneous in-place backup), incremental block-level send (can greatly reduce backup storage size if your data doesn't change often), optional transparent compression for live data (like what ntfs has). -- Fajar I am not familiar with OpenSolaris but that may change with time. -- 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.unive...@gmail.com Mobile Phone (Starhub Prepaid): +65-8369-2618 Street: Bedok Reservoir Road Country: Singapore Hi, I have just finished writing my backup/cloning script. Could anyone help me verify whether my backup script will work? SCRIPT #!/bin/sh # Script to Backup/Clone Xen Host/Dom0 and all DomUs which are using Logical Volumes as Virtual Hard Disks # Written by: # Mr. Teo En Ming (Zhang Enming) Dip(Mechatronics) BEng(Hons)(Mechanical Engineering) # Alma Maters: # (1) Singapore Polytechnic # (2) National University of Singapore # Primary Blog: http://teo-en-ming-aka-zhang-enming.blogspot.com # Secondary Blog: http://enmingteo.wordpress.com # Youtube Videos: http://www.youtube.com/user/enmingteo # Email: space.time.unive...@gmail.com # MSN: teoenm...@hotmail.com # Mobile Phone (Starhub Prepaid): +65-8369-2618 # Street: Bedok Reservoir Road # Country: Singapore # First written: 13 November 2009 Friday 12:38 A.M. Singapore time # Last updated: 13 November 2009 Friday 12:38 A.M. Singapore time # REFERNCE: Geek Sheet: Bare-metal backup and recovery, May 7th, 2008, Jason Perlow # URL: http://blogs.zdnet.com/BTL/?p=8759 # Usage Instructions: # Boot up your computer/server with System Rescue CD version 1.3.2 for i386/amd64. # Then execute this backup script. You need to adapt this script to work for your environment. # Download System Rescue CD from http://www.sysresccd.org/Main_Page ### # Declare Variables ### HARDDISK=/dev/sda DEST=/media/hitachi/test ### # Cloning Xen Host/Dom0 ### # Backup MBR dd if=$HARDDISK of=$DEST/f11-xen-dom0-sda.mbr bs=512 count=1 # Activate all logical volumes in all volume groups vgchange -ay # Backup UUIDs of PVs pvdisplay $DEST/f11-xen-dom0-pvdisplay.txt # Backup LVM Metadata # Backup the configuration of dedicated volume group for dom0 vgcfgbackup -d -v vg_fedora11_host -f $DEST/vg_fedora11_host.vgcfg.backup # Backup the configuration of dedicated volume group for domUs vgcfgbackup -d -v virtualmachines -f $DEST/virtualmachines.vgcfg.backup # Backup /boot partition and all logical volumes of dedicated volume group for host/dom0 fsarchiver savefs -v -z 9 -j 2 $DEST/f11-xen-dom0-filesystems.fsa /dev/sda1 /dev/vg_fedora11_host/lv_home \ /dev/vg_fedora11_host/lv_root /dev/vg_fedora11_host/lv_var
Re: [Xen-users] Re: How to Backup and Restore MBR within Logical Volumes?
On Fri, Nov 13, 2009 at 5:40 AM, Sergey Vlasov v...@altlinux.ru wrote: On Fri, Nov 13, 2009 at 12:57:22AM +0800, Mr. Teo En Ming (Zhang Enming) wrote: [...] # VM 11: Rocks 5.1 x86_64 HPC Compute Cluster HVM domU kpartx -av /dev/virtualmachines/rocks0001 dd if=/dev/virtualmachines/rocks0001 of=$DEST/rocks0001.mbr bs=512 count=1 partimage -d -M -b -z1 save /dev/mapper/virtualmachines-rocks0001p1 $DEST/virtualmachines-rocks0001p1.img partimage -d -M -b -z1 save /dev/mapper/virtualmachines-rocks0001p2 $DEST/virtualmachines-rocks0001p2.img partimage -d -M -b -z1 save /dev/mapper/virtualmachines-rocks0001p5 $DEST/virtualmachines-rocks0001p5.img Note that this VM (and some other VMs listed in your script) uses logical partitions. In this case just saving a copy of MBR will not be enough to save partition layout - MBR describes only 4 primary partitions, and restoring just MBR will not restore extended partitions. One way to backup the complete partition layout is by saving also the output of sfdisk -d $device; the resulting file can be used as input to sfdisk to restore all partitions, including logical ones. Saving MBR is still needed together with sfdisk, because it saves the boot code (used for HVM) and CHS geometry information (which can be used during boot in some cases). -BEGIN PGP SIGNATURE- Version: GnuPG v1.4.10 (GNU/Linux) iEYEARECAAYFAkr8gM8ACgkQW82GfkQfsqLa+QCaAqpO5NWhYHtKVi3M5ytERw27 eC0AnjsJuG34MAR1jZRejBiJCVybQvc1 =RRGH -END PGP SIGNATURE- ___ Xen-users mailing list xen-us...@lists.xensource.com http://lists.xensource.com/xen-users Thank you for pointing this out. Otherwise I would made incomplete backups. Would it be best practice to always backup both the MBR and the partition geometry using sfdisk whenever cloning our harddisks on desktops and servers? Besides sfdisk, there are also other partitioning tools like fdisk, cfdisk, and parted. Could these other tools also be used for backing up the partition geometry like sfdisk? Thank you. -- 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.unive...@gmail.com Mobile Phone (Starhub Prepaid): +65-8369-2618 Street: Bedok Reservoir Road Country: Singapore -- 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
Re: [Xen-users] Re: How to Backup and Restore MBR within Logical Volumes?
On Fri, Nov 13, 2009 at 11:17 AM, Mr. Teo En Ming (Zhang Enming) space.time.unive...@gmail.com wrote: On Fri, Nov 13, 2009 at 5:40 AM, Sergey Vlasov v...@altlinux.ru wrote: On Fri, Nov 13, 2009 at 12:57:22AM +0800, Mr. Teo En Ming (Zhang Enming) wrote: [...] # VM 11: Rocks 5.1 x86_64 HPC Compute Cluster HVM domU kpartx -av /dev/virtualmachines/rocks0001 dd if=/dev/virtualmachines/rocks0001 of=$DEST/rocks0001.mbr bs=512 count=1 partimage -d -M -b -z1 save /dev/mapper/virtualmachines-rocks0001p1 $DEST/virtualmachines-rocks0001p1.img partimage -d -M -b -z1 save /dev/mapper/virtualmachines-rocks0001p2 $DEST/virtualmachines-rocks0001p2.img partimage -d -M -b -z1 save /dev/mapper/virtualmachines-rocks0001p5 $DEST/virtualmachines-rocks0001p5.img Note that this VM (and some other VMs listed in your script) uses logical partitions. In this case just saving a copy of MBR will not be enough to save partition layout - MBR describes only 4 primary partitions, and restoring just MBR will not restore extended partitions. One way to backup the complete partition layout is by saving also the output of sfdisk -d $device; the resulting file can be used as input to sfdisk to restore all partitions, including logical ones. Saving MBR is still needed together with sfdisk, because it saves the boot code (used for HVM) and CHS geometry information (which can be used during boot in some cases). -BEGIN PGP SIGNATURE- Version: GnuPG v1.4.10 (GNU/Linux) iEYEARECAAYFAkr8gM8ACgkQW82GfkQfsqLa+QCaAqpO5NWhYHtKVi3M5ytERw27 eC0AnjsJuG34MAR1jZRejBiJCVybQvc1 =RRGH -END PGP SIGNATURE- ___ Xen-users mailing list xen-us...@lists.xensource.com http://lists.xensource.com/xen-users Thank you for pointing this out. Otherwise I would made incomplete backups. Would it be best practice to always backup both the MBR and the partition geometry using sfdisk whenever cloning our harddisks on desktops and servers? Besides sfdisk, there are also other partitioning tools like fdisk, cfdisk, and parted. Could these other tools also be used for backing up the partition geometry like sfdisk? Thank you. -- 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.unive...@gmail.com Mobile Phone (Starhub Prepaid): +65-8369-2618 Street: Bedok Reservoir Road Country: Singapore Hi, I have made some improvements to the backup/cloning script. Please help me to vet it through for any mistakes. Thank you very much! SCRIPT #!/bin/sh ### ### # Script to Backup/Clone Xen Host/Dom0 and all DomUs which are using Logical Volumes as Virtual Hard Disks ### ### # Written by: # Mr. Teo En Ming (Zhang Enming) Dip(Mechatronics) BEng(Hons)(Mechanical Engineering) # Alma Maters: # (1) Singapore Polytechnic # (2) National University of Singapore # Primary Blog: http://teo-en-ming-aka-zhang-enming.blogspot.com # Secondary Blog: http://enmingteo.wordpress.com # Youtube Videos: http://www.youtube.com/user/enmingteo # Xen Tutorials and Video Demos: http://www.xen.org/support/tutorial.html # Email: space.time.unive...@gmail.com # MSN: teoenm...@hotmail.com # Mobile Phone (Starhub Prepaid): +65-8369-2618 # Street: Bedok Reservoir Road # Country: Singapore # First written: 13 November 2009 Friday 12:38 A.M. Singapore time # Last updated: 13 November 2009 Friday 12:38 A.M. Singapore time # Last updated: 13 November 2009 Friday 1:20 P.M. Singapore time # REFERNCE: Geek Sheet: Bare-metal backup and recovery, May 7th, 2008, Jason Perlow # URL: http://blogs.zdnet.com/BTL/?p=8759 # Usage Instructions: # Boot up your desktop/server with System Rescue CD version 1.3.2 for i386/amd64. # Then execute this backup script. You need to adapt this script to work for your environment. # Download System Rescue CD from http://www.sysresccd.org/Main_Page # FAQ # Q: Why do I want to write this cloning script when there are many open source cloning software available? # A: I am previously using Clonezilla. It is a very good cloning software. However, it could not detect all the #virtual machines in my LVM2 logical volumes and had to fall back on using dd to image all my domUs, #which resulted in an enormous 300 GB (!) backup
