ZVOL boot - Revision history

95.222.158.219: /* Clone root */ Mention the noowners problem.

2025-03-03T19:13:07Z

‎Clone root: Mention the noowners problem.

Evansus: /* Create zvol */

2016-07-11T07:40:02Z

‎Create zvol

Evansus: /* Create zvol */

2016-07-11T05:13:50Z

‎Create zvol

Evansus: /* ZVOL Boot */

2016-07-11T05:10:54Z

‎ZVOL Boot

Evansus: Add boot.plist UUID requirement

2016-07-11T05:02:17Z

Add boot.plist UUID requirement

Evansus at 12:57, 6 July 2016

2016-07-06T12:57:55Z

Evansus: Created page with "=== ZVOL boot === Using the same steps to create the boot helper partition as ZFS on Boot, you may install Mac OS X onto a ZVOL device and use it as your boot volume. ==..."

2016-07-06T12:51:01Z

Created page with "=== ZVOL boot === Using the same steps to create the boot helper partition as ZFS on Boot, you may install Mac OS X onto a ZVOL device and use it as your boot volume. ==..."

New page

=== ZVOL boot ===

Using the same steps to create the boot helper partition as [[ZFS on Boot]], you may install Mac OS X onto a ZVOL device and use it as your boot volume.

==== Create zvol ====
# zfs create -sV 80g rpool/ZVOL/MacOS

Get the diskN for that device
# zvol=`ioreg -trn "ZVOL rpool/ZVOL/MacOS Media" | grep "BSD Name" | awk -F'"' '{print $4}'`
(it would be nice if we could just # zfs get zvol-disk rpool/ZVOL/MacOS)

Erase and create a volume
# diskutil eraseDisk JHFS+ MacOS ${zvol}

==== Clone root ====
Clone an existing Mac OS
# rsync -axH --exclude=".Spotlight-V100" --exclude=".fseventsd" \
--exclude=".vol" "/Volumes/Macintosh HD/" "/Volumes/MacOS/"

Or use Apple System Restore
# asr --source "/Volumes/Macintosh HD" --target "/Volumes/MacOS" --erase

==== New install ====
It is possible, but requires a few steps, to install Mac OS onto a ZVOL with the standard Apple installer.
Download the installer from the App Store, and create an installer flash drive.
Boot into the Installer, with a standard Mac OS disk available '''Macintosh HD''' (that has ZFS installed).

From '''Utilities->Terminal''' you can:
# kextload "/Volumes/Macintosh HD/Library/Extensions/spl.kext"
# kextload "/Volumes/Macintosh HD/Library/Extensions/zfs.kext"

At that point you need access to the zpool and zfs commands, which require the libzfs and libzpool libraries. To work around the install environment, simply:
# chroot "/Volumes/Macintosh HD"
# zpool import
Or if necessary
# /usr/local/sbin/zpool import

This worked with El Capitan Install 10.11 and the signed O3x from [[Downloads]].
I don't remember which version of O3x, but I believe it was 1.4.5 or so.

==== Setup boot helper ====
See [[Boot.plist]] for sample plist files.

@@ Line 24: / Line 24: @@
 With partition map:
   # diskutil eraseDisk JHFS+ MacOS ${zvol}
 Without partitions:

← Older revision		Revision as of 05:10, 11 July 2016
Line 2:		Line 2:

	Using the same steps to create the boot helper partition as [[ZFS on Boot]], you may install Mac OS X onto a ZVOL device and use it as your boot volume.		Using the same steps to create the boot helper partition as [[ZFS on Boot]], you may install Mac OS X onto a ZVOL device and use it as your boot volume.
		+
		+	==== Disable bootfs ====
		+
		+	zvol boot does not currently co-exist with zfs boot (planned to be fixed). The presence of the '''bootfs''' property will take precedence at boot time.
		+
		+	You will need to clear bootfs when using zvol boot:
		+
		+	# <nowiki>sudo zpool set bootfs='' poolname</nowiki>
		+
		+	Using two single quotes will remove the previous bootfs.

	==== Create zvol ====		==== Create zvol ====

← Older revision		Revision as of 05:02, 11 July 2016
Line 40:		Line 40:

	==== Setup boot helper ====		==== Setup boot helper ====
		+
		+	Boot helper can be setup similar to the boot helper for [[ZFS on Boot]] with some differences.
		+
		+	Root UUID must be set to the Volume UUID of the zvol. You can retrieve this by:
		+
		+	# diskutil info diskN \| grep "Volume UUID"
		+
		+	For a volume directly within a zvol, or
		+
		+	# diskutil info diskNsN \| grep "Volume UUID"
		+
		+	For a zvol with a partition map.
		+
		+	Kernel Flags should contain "zfs_boot=poolname"
		+
	See [[Boot.plist]] for sample plist files.		See [[Boot.plist]] for sample plist files.
		+
		+	At this time zfs_boot=poolname/zvol or poolname/dataset/zvol will only import the zpool "poolname" and does not check or mount the zvol specified. Correctly setting Root UUID to match will inform the OS to locate the root volume.
		+
		+	In the future, it will be possible to specify a zvol by name, which will then be inspected for matching volume UUID and presented for mount. This would prevent any duplicate UUID clashes due to `zfs clone` copies. To do so will require an additional property zfs_root_uuid=<uuid>, or perhaps zfs_root_partition=N, so that the OS does not try to automatically load the first matching volume.

← Older revision		Revision as of 12:57, 6 July 2016
Line 1:		Line 1:
−	=== ZVOL ~~boot~~ ===	+	=== ZVOL Boot ===

	Using the same steps to create the boot helper partition as [[ZFS on Boot]], you may install Mac OS X onto a ZVOL device and use it as your boot volume.		Using the same steps to create the boot helper partition as [[ZFS on Boot]], you may install Mac OS X onto a ZVOL device and use it as your boot volume.

@@ Line 33: / Line 33: @@
 ==== Clone root ====
 Clone an existing Mac OS
   # rsync -axH --exclude=".Spotlight-V100" --exclude=".fseventsd" \