Cloning file system - Revision history

Ch at 15:51, 9 March 2026

2026-03-09T15:51:21Z

← Older revision		Revision as of 15:51, 9 March 2026
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	;:edit <tt>grub.cfg</tt> on <tt>/boot/efi</tt>		;:edit <tt>grub.cfg</tt> on <tt>/boot/efi</tt>
	:<tt>sudo emacs /media/USB/sdb1~~/efi~~/EFI/ubuntu/grub.cfg</tt>		:<tt>sudo emacs /media/USB/sdb1/EFI/ubuntu/grub.cfg</tt>
	::& change the line which looks like		::& change the line which looks like
	:::<tt>search.fs_uuid 96b8896d-0474-48c4-9976-f71e754b7ca4 root hd0,gpt4 </tt>		:::<tt>search.fs_uuid 96b8896d-0474-48c4-9976-f71e754b7ca4 root hd0,gpt4 </tt>

2026-02-28T11:24:13Z

← Older revision		Revision as of 11:24, 28 February 2026
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	;:edit <tt>grub.cfg</tt> on <tt>/boot/efi</tt>		;:edit <tt>grub.cfg</tt> on <tt>/boot/efi</tt>
	:<tt>sudo emacs /media/USB/sdb1/efi/EFI/ubuntu/grub.cfg</tt>		:<tt>sudo emacs /media/USB/sdb1/efi/EFI/ubuntu/grub.cfg</tt>
	::& change the line		::& change the line which looks like
	:::<tt>search.fs_uuid 96b8896d-0474-48c4-9976-f71e754b7ca4 root hd0,gpt4 </tt>		:::<tt>search.fs_uuid 96b8896d-0474-48c4-9976-f71e754b7ca4 root hd0,gpt4 </tt>
	::and insert the new uuid generated previously		::and insert the new uuid generated previously

2026-02-28T11:22:50Z

← Older revision		Revision as of 11:22, 28 February 2026
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	;:modify uuid of <tt>/dev/sda1</tt> which will be mounted as <tt>/boot/efi</tt>		;:modify uuid of <tt>/dev/sda1</tt> which will be mounted as <tt>/boot/efi</tt>
	::not sure how to do this reliably as yet - but probably doesn't matter		::not sure how to do this reliably as yet - but probably doesn't matter. The disk selected from the boot source options at startup will be /<tt>dev/sda</tt> and its first partition <tt>/dev/sda1</tt>

	;:modify uuid of <tt>/dev/sda2</tt> which will be mounted as <tt>/boot</tt>		;:modify uuid of <tt>/dev/sda2</tt> which will be mounted as <tt>/boot</tt>
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	;boot		;boot
	::Start the old mac laptop, pressing the option key to show boot menu		::Start the old mac laptop, pressing the option key during startup to show boot menu

2026-02-28T11:19:45Z

← Older revision		Revision as of 11:19, 28 February 2026
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	:<tt>sudo mount /dev/sdb2 /media/USB/sdb2</tt>		:<tt>sudo mount /dev/sdb2 /media/USB/sdb2</tt>
	:<tt>sudo mount /dev/mapper/ubuntu--vg--clone-ubuntu--lv /media/USB/sdb3</tt>		:<tt>sudo mount /dev/mapper/ubuntu--vg--clone-ubuntu--lv /media/USB/sdb3</tt>

			::mark disk
			Create file on root of disk to identify it easily as it could be mounted as /dev/sda, /dev/sdb etc, e.g.
			:<tt>sudo touch /disk_is_external</tt>

	;to boot from clone		;to boot from clone

2026-02-15T13:45:13Z

← Older revision		Revision as of 13:45, 15 February 2026
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	::& and add a new <tt>menuentry</tt> section (or edit the existing one) so that the referenced uuids point to the uuids of the cloned disk		::& and add a new <tt>menuentry</tt> section (or edit the existing one) so that the referenced uuids point to the uuids of the cloned disk
	::& and modify the line starting <tt>linux</tt> to point to the cloned logical volume instead		::& and modify the line starting <tt>linux</tt> to point to the cloned logical volume instead


			;boot
			::Start the old mac laptop, pressing the option key to show boot menu

2026-02-15T13:43:01Z

← Older revision		Revision as of 13:43, 15 February 2026
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	;:edit grub.cfg on /boot/efi		;:edit <tt>grub.cfg</tt> on <tt>/boot/efi</tt>
	:<tt>sudo emacs /~~boot~~/efi/EFI/ubuntu/grub.cfg</tt>		:<tt>sudo emacs /media/USB/sdb1/efi/EFI/ubuntu/grub.cfg</tt>
	::& change the line		::& change the line
	:::<tt>search.fs_uuid 96b8896d-0474-48c4-9976-f71e754b7ca4 root hd0,gpt4 </tt>		:::<tt>search.fs_uuid 96b8896d-0474-48c4-9976-f71e754b7ca4 root hd0,gpt4 </tt>
	::and insert the new uuid generated previously		::and insert the new uuid generated previously

			;:edit <tt>grub.cfg</tt> on <tt>/boot</tt>
			:sudo emacs /media/USB/sdb2/grub/grub.cfg</tt>
			::& and add a new <tt>menuentry</tt> section (or edit the existing one) so that the referenced uuids point to the uuids of the cloned disk
			::& and modify the line starting <tt>linux</tt> to point to the cloned logical volume instead

2026-02-15T13:33:18Z

← Older revision		Revision as of 13:33, 15 February 2026
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	;:modify uuid of <tt>/dev/sda2</tt> which will be mounted as <tt>/boot</tt>		;:modify uuid of <tt>/dev/sda2</tt> which will be mounted as <tt>/boot</tt>
			:<tt>sudo uuidgen</tt>
			::to generate and display a new random uuid number
			:<tt>sudo tune2fs -U <new_uuid> /dev/sdb2</tt>
			::where <tt><new_uuid></tt> is the new uuid displayed earlier


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	:<tt>sudo emacs /boot/efi/EFI/ubuntu/grub.cfg</tt>		:<tt>sudo emacs /boot/efi/EFI/ubuntu/grub.cfg</tt>
	::& change the line		::& change the line
			:::<tt>search.fs_uuid 96b8896d-0474-48c4-9976-f71e754b7ca4 root hd0,gpt4 </tt>
			::and insert the new uuid generated previously

2026-02-15T11:38:51Z

← Older revision		Revision as of 11:38, 15 February 2026
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	::mount		::mount
	:<tt>sudo mount /dev/mapper/ubuntu--vg--clone-ubuntu--lv /media/USB/~~sdd3~~</tt>		:<tt>sudo mount /dev/sdb1 /media/USB/sdb1</tt>
			:<tt>sudo mount /dev/sdb2 /media/USB/sdb2</tt>
			:<tt>sudo mount /dev/mapper/ubuntu--vg--clone-ubuntu--lv /media/USB/sdb3</tt>

			;to boot from clone
			the principle is to change uuid of disks and modify <tt>grub.cfg</tt> files to reflect this. There appears to be a <tt>grub.cfg</tt> in both <tt>/boot/efi</tt> (which is separate VFAT partition on my system) and in <tt>/boot/grub</tt> (which is the ext4 boot partition). Note that the external disk is listed as <tt>/dev/sdb</tt> when we have booted normally. If we attempt to boot from the external disk it will be listed as <tt>/dev/sda</tt>

			;: to find current uuids a number of commands show them
			:<tt>sudo blkid</tt>
			::lists the physical uuids of the disks
			:<tt>sudo pvdisplay</tt>
			:<tt>sudo vgdisplay</tt>
			:<tt>sudo lvdisplay</tt>
			::will display the lvm physical and logical groups and logical volumes respectively

			;:modify uuid of <tt>/dev/sda1</tt> which will be mounted as <tt>/boot/efi</tt>
			::not sure how to do this reliably as yet - but probably doesn't matter

			;:modify uuid of <tt>/dev/sda2</tt> which will be mounted as <tt>/boot</tt>


			;:edit grub.cfg on /boot/efi
			:<tt>sudo emacs /boot/efi/EFI/ubuntu/grub.cfg</tt>
			::& change the line

2026-02-11T15:12:40Z

← Older revision		Revision as of 15:12, 11 February 2026
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	;to clone file system		;to clone file system
	use dd to clone disk, e.g.		use dd to clone disk, e.g.
	:<tt>sudo dd if=/dev/sda of=/dev/sdb bs=4M conv=noerror,sync status=progress</tt>		:<tt>sudo dd if=/dev/sda of=/dev/sdb bs=4M conv=noerror,sync status=progress</tt>

2026-02-11T11:12:29Z

← Older revision		Revision as of 11:12, 11 February 2026
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	principle is that the cloned volume needs to renamed before it can be mounted		principle is that the cloned volume needs to renamed before it can be mounted

	:rename volume		::rename volume
	:<tt>sudo vgimportclone --basevgname ubuntu-vg-clone /dev/sdd3</tt>		:<tt>sudo vgimportclone --basevgname ubuntu-vg-clone /dev/sdd3</tt>

	:activate		::activate
	:<tt>sudo lvchange -a y 'ubuntu-vg-clone/ubuntu-lv'</tt>		:<tt>sudo lvchange -a y 'ubuntu-vg-clone/ubuntu-lv'</tt>

	:mount		::mount
	<tt>sudo mount /dev/mapper/ubuntu--vg--clone-ubuntu--lv /media/USB/sdd3</tt>		:<tt>sudo mount /dev/mapper/ubuntu--vg--clone-ubuntu--lv /media/USB/sdd3</tt>