Immutable root with atomic upgrades - Revision history

Prabuanand: fixed category name

2024-09-13T03:59:18Z

fixed category name

← Older revision		Revision as of 03:59, 13 September 2024
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	</pre>		</pre>

	[[Category:Installation]][[Category:~~File systems~~]]		[[Category:Installation]][[Category:Filesystems]]

Mvsn: Improved sysmut script

2023-11-30T09:32:59Z

Improved sysmut script

← Older revision		Revision as of 09:32, 30 November 2023
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	foreground {		foreground {
	foreground { mount -o bind,ro /etc/resolv.conf ${mnt}/snapshots/${newsnap}/@/etc/resolv.conf }		foreground { mount -o bind,ro /etc/resolv.conf ${mnt}/snapshots/${newsnap}/@/etc/resolv.conf }
	if {		foreground {
	chroot ${mnt}/snapshots/${newsnap}/@		chroot ${mnt}/snapshots/${newsnap}/@
	foreground { mount -a }		foreground { mount -a }
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	exit ${apply}		exit ${apply}
	}		}
			importas apply ?
	foreground { redirfd -w 2 /dev/null umount ${mnt}/snapshots/${newsnap}/@/etc/resolv.conf }		foreground { redirfd -w 2 /dev/null umount ${mnt}/snapshots/${newsnap}/@/etc/resolv.conf }
	if { btrfs property set -ts ${mnt}/snapshots/${newsnap}/@ ro true }		ifelse { exit ${apply} } {
	define newlink ${dt}${rnd}		if { btrfs property set -ts ${mnt}/snapshots/${newsnap}/@ ro true }
	if { mkdir -p ${mnt}/links/${newlink} }		define newlink ${dt}${rnd}
	if { ln -s ../../snapshots/${newsnap} ${mnt}/links/${newlink}/0 }		if { mkdir -p ${mnt}/links/${newlink} }
	if { cp -P ${mnt}/current/0 ${mnt}/links/${newlink}/1 }		if { ln -s ../../snapshots/${newsnap} ${mnt}/links/${newlink}/0 }
	if { cp -P ${mnt}/current/1 ${mnt}/links/${newlink}/2 }		if { cp -P ${mnt}/current/0 ${mnt}/links/${newlink}/1 }
	if { cp -P ${mnt}/current/2 ${mnt}/links/${newlink}/3 }		if { cp -P ${mnt}/current/1 ${mnt}/links/${newlink}/2 }
	if { mkdir -p ${mnt}/next }		if { cp -P ${mnt}/current/2 ${mnt}/links/${newlink}/3 }
	if { ln -sfn ./links/${newlink} ${mnt}/next/current }		if { mkdir -p ${mnt}/next }
	if { mv ${mnt}/next/current ${mnt}/ }		if { ln -sfn ./links/${newlink} ${mnt}/next/current }
	echo "~~Switched to the new snapshot~~"		if { mv ${mnt}/next/current ${mnt}/ }
			echo "Changes applied"
			}
			echo "Changes discarded"
	}		}
	foreground { redirfd -w 2 /dev/null umount ${mnt}/snapshots/${newsnap}/@/proc }		foreground { redirfd -w 2 /dev/null umount ${mnt}/snapshots/${newsnap}/@/proc }
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	</pre>		</pre>

	It will get you into the root shell chrooted into the new snapshot, where you can apply any change you like.<br>		It will get you into the root shell chrooted into the new snapshot, where you can apply any change you like. The origin of the new snapshot is defined by the first and only argument, in form of number. If no argument provided the <code>0</code> (current latest) is taken as origin.<br>
	If chroot shell exits with an error, there will be no switch to the new snapshots. This means you can manually discard changes while in the chroot by:		If chroot shell exits with an error, there will be no switch to the new snapshots. This means you can manually discard changes while in the chroot by:

Krum: Correct some spelling and grammar mistakes, minor changes to wording in some areas

2023-11-30T08:48:24Z

Correct some spelling and grammar mistakes, minor changes to wording in some areas

Show changes

Mvsn: Add GRUB as an alternative bootloader

2023-11-21T17:13:54Z

Add GRUB as an alternative bootloader

@@ Line 1: / Line 1: @@
 === What? ===
-This article provides a basic guide to setting up a read-only-root-based Alpine Linux system with several boot environments and atomic upgrades using rEFInd and [[BTRFS|btrfs]].
+This article provides a basic guide to setting up a read-only-root-based Alpine Linux system with several boot environments and atomic upgrades using a modern bootloader and [[BTRFS|btrfs]].
 === Why? ===
@@ Line 171: / Line 171: @@
 = Bootloader installation =
 Mount the EFI partition:
 <pre># mount -t vfat /dev/sda1 /mnt
 # mkdir /mnt/EFI</pre>
 Check the latest version number of the <code>refind</code> package:
 <pre># apk info -X https://dl-cdn.alpinelinux.org/alpine/edge/testing -U refind</pre>
@@ Line 214: / Line 217: @@
 }</pre>
 {{Note|<code>"ROOT"</code> is the <code>PARTLABEL</code> of the [[BTRFS|btrfs]] partition. You may also use <code>PARTUUID</code> instead. To get both <code>blkid</code> from <code>blkid</code> package can be used. <code>blkid</code> included in busybox does not provide this information. }}
-To add rEFInd to UEFI, <code>efibootmgr</code> is a suitable tool:
+=== GRUB ===
 <pre># apk add efibootmgr
 # efibootmgr --create --disk /dev/sda --part 1 --loader /EFI/refind/refind_x64.efi --label "rEFInd" --verbose</pre>
-<code>/dev/sda</code> is our disk device and <code>1</code> is the number of partition containing <code>rEFInd</code>.
+<code>/dev/sda</code> is our disk device and <code>1</code> is the number of the FAT32 partition containing the bootloader data.
 = Updating or altering the system =

Mvsn: simplify setup by using common non-snapshotted /var

2023-11-04T18:41:59Z

simplify setup by using common non-snapshotted /var

← Older revision		Revision as of 18:41, 4 November 2023
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	Stores common non-snapshotting subvolumes.<br>		Stores common non-snapshotting subvolumes.<br>
	We may populate it right away:		We may populate it right away:
	<pre># btrfs subvolume create /mnt/commons/@var~~@tmp~~		<pre># btrfs subvolume create /mnt/commons/@var
	~~# btrfs subvolume create /mnt/commons/@var@cache~~
	~~# btrfs subvolume create /mnt/commons/@var@log~~
	# btrfs subvolume create /mnt/commons/@home</pre>		# btrfs subvolume create /mnt/commons/@home</pre>
	~~If you use flatpak, you may also want to keep it's directory separate:~~
	~~<pre># btrfs subvolume create /mnt/commons/@var@lib@flatpak</pre>~~
	~~Include anything else in <code>/var</code> that should be mutable, for example iwd and bluetooth:~~
	~~<pre># btrfs subvolume create /mnt/commons/@var@lib@iwd~~
	~~# btrfs subvolume create /mnt/commons/@var@lib@bluetooth</pre>~~
	Next, most important directories:		Next, most important directories:
	<pre># mkdir /mnt/snapshots</pre>		<pre># mkdir /mnt/snapshots</pre>
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	Example:		Example:
	<pre>UUID=b9ff5e7b-e128-4e64-861a-2fdd794a9828 / btrfs subvol=CURRENT_SNAPSHOTS_PATH/@,ro,noatime 0 0		<pre>UUID=b9ff5e7b-e128-4e64-861a-2fdd794a9828 / btrfs subvol=CURRENT_SNAPSHOTS_PATH/@,ro,noatime 0 0
	UUID=b9ff5e7b-e128-4e64-861a-2fdd794a9828 /var~~/tmp~~ btrfs subvol=/commons/@var~~@tmp,rw,noatime 0 0~~		UUID=b9ff5e7b-e128-4e64-861a-2fdd794a9828 /var btrfs subvol=/commons/@var,rw,noatime 0 0
	~~UUID=b9ff5e7b-e128-4e64-861a-2fdd794a9828 /var/cache btrfs subvol=/commons/@var@cache,rw,noatime 0 0~~
	~~UUID=b9ff5e7b-e128-4e64-861a-2fdd794a9828 /var/log btrfs subvol=/commons/@var@log,rw,noatime 0 0~~
	~~UUID=b9ff5e7b-e128-4e64-861a-2fdd794a9828 /var/lib/flatpak btrfs subvol=/commons/@var@lib@flatpak,rw,noatime 0 0~~
	~~UUID=b9ff5e7b-e128-4e64-861a-2fdd794a9828 /var/lib/iwd btrfs subvol=/commons/@var@lib@iwd,rw,noatime 0 0~~
	~~UUID=b9ff5e7b-e128-4e64-861a-2fdd794a9828 /var/lib/bluetooth btrfs subvol=/commons/@var@lib@bluetooth~~,rw,noatime 0 0
	UUID=b9ff5e7b-e128-4e64-861a-2fdd794a9828 /home btrfs subvol=/commons/@home,rw,noatime 0 0		UUID=b9ff5e7b-e128-4e64-861a-2fdd794a9828 /home btrfs subvol=/commons/@home,rw,noatime 0 0
	# UUID=2FE6-837A /boot/efi vfat rw,noatime,discard 0 2		# UUID=2FE6-837A /boot/efi vfat rw,noatime,discard 0 2
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	<pre>\|--mnt		<pre>\|--mnt
	\| \|--commons		\| \|--commons
	\| \| \|--@var~~@tmp~~		\| \| \|--@var
	~~\| \| \|--@var@cache~~
	~~\| \| \|--@var@log~~
	~~\| \| \|--@var@lib@flatpak~~
	~~\| \| \|--@var@lib@iwd~~
	\| \| \|--@home		\| \| \|--@home
	\| \|--current		\| \|--current

Mvsn: add notes and warnings for some steps

2023-11-04T18:22:54Z

add notes and warnings for some steps

← Older revision		Revision as of 18:22, 4 November 2023
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	<pre># mv refind.conf-sample refind.conf		<pre># mv refind.conf-sample refind.conf
	# vi refind.conf</pre>		# vi refind.conf</pre>
	And append following to the end of the file, remember to replace example UUIDs with your own for <code>root</code> ([[BTRFS\|btrfs]] partition) and <code>resume</code> (swap partition):		And append following to the end of the file, remember to replace example UUIDs with your own for <code>root</code> ([[BTRFS\|btrfs]] partition) and <code>resume</code> (swap partition). Keep in mind that if you named the btrfs volume other than <code>ROOT</code> during "Partitioning disks" stage, you have to change the <code>volume</code> field below accordingly.
	<pre>		<pre>
	menuentry "Alpine Linux" {		menuentry "Alpine Linux" {
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	= Updating or altering the system =		= Updating or altering the system =
	{{~~Note~~\|These examples are implemented using execline and require <code>execline</code> package in the system. These could surely be implemented in POSIX shell, however execline provides number of runtime advantages and is much more readable.}}		{{Warning\|Without the following step or an alternative you will have no easy way to mutate the installed system.}}
			{{Warning\|These examples are implemented using <code>execline</code> and require the <code>execline</code> package in the system.}}
			{{Note\|These could surely be implemented in POSIX shell, however <code>execline</code> provides number of runtime advantages and the script in it is much more readable.}}
	<pre># touch /usr/sbin/sysmut		<pre># touch /usr/sbin/sysmut
	# chmod +x /usr/sbin/sysmut		# chmod +x /usr/sbin/sysmut

Zcrayfish: Added cats

2023-09-04T19:34:13Z

Added cats

← Older revision		Revision as of 19:34, 4 September 2023
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	...		...
	</pre>		</pre>

			[[Category:Installation]][[Category:File systems]]

Machinestops: Bluetooth persisting settings across reboots requires a mutable /var/lib/bluetooth. Introduce this alongside iwd.

2023-05-31T15:59:43Z

Bluetooth persisting settings across reboots requires a mutable /var/lib/bluetooth. Introduce this alongside iwd.

Mvsn at 08:39, 6 February 2022

2022-02-06T08:39:01Z

← Older revision		Revision as of 08:39, 6 February 2022
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	<pre># touch /usr/sbin/sysmut		<pre># touch /usr/sbin/sysmut
	# chmod +x /usr/sbin/sysmut		# chmod +x /usr/sbin/sysmut
	# vi /sbin/sysmut</pre>		# vi /usr/sbin/sysmut</pre>

	Example script to mutate the the system:		Example script to mutate the the system:
Line 305:		Line 305:
	Unused snapshots can be garbage-collected by:		Unused snapshots can be garbage-collected by:

	<pre># touch /sbin/syscln		<pre># touch /usr/sbin/syscln
	# chmod +x /sbin/syscln		# chmod +x /usr/sbin/syscln
	# vi /sbin/syscln</pre>		# vi /usr/sbin/syscln</pre>

	<pre>#!/bin/execlineb -W		<pre>#!/bin/execlineb -W

Mvsn at 22:10, 5 February 2022

2022-02-05T22:10:16Z

← Older revision		Revision as of 22:10, 5 February 2022
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	# mkdir /mnt/EFI</pre>		# mkdir /mnt/EFI</pre>
	Check the latest version number of the <code>refind</code> package:		Check the latest version number of the <code>refind</code> package:
	<pre># apk info -U refind</pre>		<pre># apk info -X https://dl-cdn.alpinelinux.org/alpine/edge/testing -U refind</pre>
	Download the latest version (replace 0.13.2-r3 in the example below) of the <code>refind</code> package:		Download the latest version (replace 0.13.2-r3 in the example below) of the <code>refind</code> package:
	<pre># wget https://dl-cdn.alpinelinux.org/alpine/edge/testing/x86_64/refind-0.13.2-r3.apk</pre>		<pre># wget https://dl-cdn.alpinelinux.org/alpine/edge/testing/x86_64/refind-0.13.2-r3.apk</pre>

← Older revision		Revision as of 15:59, 31 May 2023
Line 55:		Line 55:
	If you use flatpak, you may also want to keep it's directory separate:		If you use flatpak, you may also want to keep it's directory separate:
	<pre># btrfs subvolume create /mnt/commons/@var@lib@flatpak</pre>		<pre># btrfs subvolume create /mnt/commons/@var@lib@flatpak</pre>
	Include anything else in <code>/var</code> that should be mutable, for example:		Include anything else in <code>/var</code> that should be mutable, for example iwd and bluetooth:
	<pre># btrfs subvolume create /mnt/commons/@var@lib@iwd</pre>		<pre># btrfs subvolume create /mnt/commons/@var@lib@iwd
			# btrfs subvolume create /mnt/commons/@var@lib@bluetooth</pre>
	Next, most important directories:		Next, most important directories:
	<pre># mkdir /mnt/snapshots</pre>		<pre># mkdir /mnt/snapshots</pre>
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	UUID=b9ff5e7b-e128-4e64-861a-2fdd794a9828 /var/lib/flatpak btrfs subvol=/commons/@var@lib@flatpak,rw,noatime 0 0		UUID=b9ff5e7b-e128-4e64-861a-2fdd794a9828 /var/lib/flatpak btrfs subvol=/commons/@var@lib@flatpak,rw,noatime 0 0
	UUID=b9ff5e7b-e128-4e64-861a-2fdd794a9828 /var/lib/iwd btrfs subvol=/commons/@var@lib@iwd,rw,noatime 0 0		UUID=b9ff5e7b-e128-4e64-861a-2fdd794a9828 /var/lib/iwd btrfs subvol=/commons/@var@lib@iwd,rw,noatime 0 0
			UUID=b9ff5e7b-e128-4e64-861a-2fdd794a9828 /var/lib/bluetooth btrfs subvol=/commons/@var@lib@bluetooth,rw,noatime 0 0
	UUID=b9ff5e7b-e128-4e64-861a-2fdd794a9828 /home btrfs subvol=/commons/@home,rw,noatime 0 0		UUID=b9ff5e7b-e128-4e64-861a-2fdd794a9828 /home btrfs subvol=/commons/@home,rw,noatime 0 0
	# UUID=2FE6-837A /boot/efi vfat rw,noatime,discard 0 2		# UUID=2FE6-837A /boot/efi vfat rw,noatime,discard 0 2