benitogf · July 19, 2025 19:01 · enoch85 · Aug 4, 2023 · benitogf · Aug 9, 2023
diff --git a/mirror.sh b/mirror.sh
 #!/bin/sh

 # Assumptions and requirements
 # - All drives will be formatted. These instructions are not suitable for dual-boot
 # - No hardware or software RAID is to be used, these would keep ZFS from detecting disk errors and correcting them. In UEFI settings, set controller mode to AHCI, not RAID
 # - These instructions are specific to UEFI systems and GPT. If you have an older BIOS/MBR system, please use https://openzfs.github.io/openzfs-docs/Getting%20Started/Ubuntu/Ubuntu%2020.04%20Root%20on%20ZFS.html

 # change the these disks variables to your disks paths (check with  lsblk)
 DISK1="/dev/nvme0n1"
 DISK2="/dev/nvme1n1"

 if [ "$(id -u)" -ne 0 ]; then
    echo "Please run this script with sudo:"
    echo "sudo $0 $*"
    exit 1
 fi

 echo "Installing dependencies"
 apt install -y gdisk mdadm grub-efi-amd64

 echo "-- Create partitions on second drive"

 echo "Change swap partition type"
 sgdisk -t2:FD00 $DISK1

 echo "Copy partition table from disk 1 to disk 2"
 sgdisk -R $DISK2 $DISK1

 echo "Change GUID of second disk"
 sgdisk -G $DISK2

 # this change seems to take a while to propagate :/
 sleep 1

 echo "-- Mirror boot pool"

 echo "Get GUID of partition 3 on disk 2"
 DISK1_PART3_GUID=$(sgdisk -i3 $DISK1 |  grep "^Partition unique GUID:" | awk '{print tolower($4)}')
 DISK2_PART3_GUID=$(sgdisk -i3 $DISK2 |  grep "^Partition unique GUID:" | awk '{print tolower($4)}')
 echo "DISK 1 PART 3 GUID"
 echo $DISK1_PART3_GUID
 echo "DISK 2 PART 3 GUID"
 echo $DISK2_PART3_GUID

 if [ -z  $DISK1_PART3_GUID ]; then
    echo "error: failed to get the disk1 part 3 guid"
    exit 1
 fi

 if [ -z  $DISK2_PART3_GUID ]; then
    echo "error: failed to get the disk2 part 3 guid"
    exit 1
 fi

 echo "attach partition to bpool"
 zpool attach bpool $DISK1_PART3_GUID /dev/disk/by-partuuid/$DISK2_PART3_GUID || exit 1

 # TODO: check for failure here by the zpool status not showing the mirror

 echo "-- Mirror root pool"

 DISK1_PART4_GUID=$(sgdisk -i4 $DISK1 |  grep "^Partition unique GUID:" | awk '{print tolower($4)}')
 DISK2_PART4_GUID=$(sgdisk -i4 $DISK2 |  grep "^Partition unique GUID:" | awk '{print tolower($4)}')

 if [ -z  $DISK1_PART4_GUID ]; then
    echo "error: failed to get the disk1 part 4 guid"
    exit 1
 fi

 if [ -z  $DISK2_PART4_GUID ]; then
    echo "error: failed to get the disk2 part 4 guid"
    exit 1
 fi

 echo "attach partition to rpool"
 zpool attach rpool $DISK1_PART4_GUID /dev/disk/by-partuuid/$DISK2_PART4_GUID || exit 1

 # TODO: check for failure here by the zpool status not showing the mirror

 echo "-- Mirror Swap"

 echo "remove existing swap"
 swapoff -a || exit 1

 echo "remove the swap mount line in /etc/fstab"
 sed -i '/swap/d' /etc/fstab

 echo "create software mirror drive for swap"
 mdadm --create /dev/md0 --metadata=1.2 --level=mirror --raid-devices=2 ${DISK1}p2 ${DISK2}p2 || exit 1

 echo "configure mirror drive for swap"
 mkswap -f /dev/md0 || exit 1

 echo "place mirror swap in fstab"
 sh -c "echo UUID=$(sudo blkid -s UUID -o value /dev/md0) none swap discard 0 0 >> /etc/fstab"

 # TODO: verify that line is in fstab cat /etc/fstab

 echo "use the new swap"
 swapon -a || exit 1

 echo "-- Move grub menu to ZFS"

 # TODO: verify that grub can  see the ZFS boot pool grub-probe /boot

 echo "create EFI file system on second disk"
 mkdosfs -F 32 -s 1 -n EFI ${DISK2}p1

 echo "remove /boot/grub from fstab"
 sed -i '/grub/d' /etc/fstab

 echo "umount /boot/grub"
 umount /boot/grub

 # TODO: Verify with df -h, /boot should be mounted on bpool/BOOT/ubuntu_UID, /boot/efi on /dev/sda1 or similar depending on device name of your first disk, and no /boot/grub

 echo "remove /boot/grub"
 rm -rf /boot/grub

 echo "create ZFS datatset for grub"
 zfs create -o com.ubuntu.zsys:bootfs=no bpool/grub

 echo "refresh initrd files"
 update-initramfs -c -k all

 echo "disable memory zeroing to address a performance regression of ZFS on linux"
 sed -i.bak "s/GRUB_CMDLINE_LINUX_DEFAULT=\"quiet splash\"/GRUB_CMDLINE_LINUX_DEFAULT=\"quiet splash init_on_alloc=0\"/g" /etc/default/grub

 echo "update grub"
 update-grub

 echo "reload daemon"
 systemctl daemon-reload

 echo "install grub to the esp"
 grub-install --target=x86_64-efi --efi-directory=/boot/efi --bootloader-id=ubuntu --recheck --no-floppy

 echo "disable grub-initrd-fallback.service"
 systemctl mask grub-initrd-fallback.service

 echo "DONE without errors"

 dpkg-reconfigure grub-efi-amd64
	#!/bin/sh

	# Assumptions and requirements
	# - All drives will be formatted. These instructions are not suitable for dual-boot
	# - No hardware or software RAID is to be used, these would keep ZFS from detecting disk errors and correcting them. In UEFI settings, set controller mode to AHCI, not RAID
	# - These instructions are specific to UEFI systems and GPT. If you have an older BIOS/MBR system, please use https://openzfs.github.io/openzfs-docs/Getting%20Started/Ubuntu/Ubuntu%2020.04%20Root%20on%20ZFS.html

	# change the these disks variables to your disks paths (check with lsblk)
	DISK1="/dev/nvme0n1"
	DISK2="/dev/nvme1n1"

	if [ "$(id -u)" -ne 0 ]; then
	echo "Please run this script with sudo:"
	echo "sudo $0 $*"
	exit 1
	fi

	echo "Installing dependencies"
	apt install -y gdisk mdadm grub-efi-amd64

	echo "-- Create partitions on second drive"

	echo "Change swap partition type"
	sgdisk -t2:FD00 $DISK1

	echo "Copy partition table from disk 1 to disk 2"
	sgdisk -R $DISK2 $DISK1

	echo "Change GUID of second disk"
	sgdisk -G $DISK2

	# this change seems to take a while to propagate :/
	sleep 1

	echo "-- Mirror boot pool"

	echo "Get GUID of partition 3 on disk 2"
	DISK1_PART3_GUID=$(sgdisk -i3 $DISK1 \| grep "^Partition unique GUID:" \| awk '{print tolower($4)}')
	DISK2_PART3_GUID=$(sgdisk -i3 $DISK2 \| grep "^Partition unique GUID:" \| awk '{print tolower($4)}')
	echo "DISK 1 PART 3 GUID"
	echo $DISK1_PART3_GUID
	echo "DISK 2 PART 3 GUID"
	echo $DISK2_PART3_GUID

	if [ -z $DISK1_PART3_GUID ]; then
	echo "error: failed to get the disk1 part 3 guid"
	exit 1
	fi

	if [ -z $DISK2_PART3_GUID ]; then
	echo "error: failed to get the disk2 part 3 guid"
	exit 1
	fi

	echo "attach partition to bpool"
	zpool attach bpool $DISK1_PART3_GUID /dev/disk/by-partuuid/$DISK2_PART3_GUID \|\| exit 1

	# TODO: check for failure here by the zpool status not showing the mirror

	echo "-- Mirror root pool"

	DISK1_PART4_GUID=$(sgdisk -i4 $DISK1 \| grep "^Partition unique GUID:" \| awk '{print tolower($4)}')
	DISK2_PART4_GUID=$(sgdisk -i4 $DISK2 \| grep "^Partition unique GUID:" \| awk '{print tolower($4)}')

	if [ -z $DISK1_PART4_GUID ]; then
	echo "error: failed to get the disk1 part 4 guid"
	exit 1
	fi

	if [ -z $DISK2_PART4_GUID ]; then
	echo "error: failed to get the disk2 part 4 guid"
	exit 1
	fi

	echo "attach partition to rpool"
	zpool attach rpool $DISK1_PART4_GUID /dev/disk/by-partuuid/$DISK2_PART4_GUID \|\| exit 1

	# TODO: check for failure here by the zpool status not showing the mirror

	echo "-- Mirror Swap"

	echo "remove existing swap"
	swapoff -a \|\| exit 1

	echo "remove the swap mount line in /etc/fstab"
	sed -i '/swap/d' /etc/fstab

	echo "create software mirror drive for swap"
	mdadm --create /dev/md0 --metadata=1.2 --level=mirror --raid-devices=2 ${DISK1}p2 ${DISK2}p2 \|\| exit 1

	echo "configure mirror drive for swap"
	mkswap -f /dev/md0 \|\| exit 1

	echo "place mirror swap in fstab"
	sh -c "echo UUID=$(sudo blkid -s UUID -o value /dev/md0) none swap discard 0 0 >> /etc/fstab"

	# TODO: verify that line is in fstab cat /etc/fstab

	echo "use the new swap"
	swapon -a \|\| exit 1

	echo "-- Move grub menu to ZFS"

	# TODO: verify that grub can see the ZFS boot pool grub-probe /boot

	echo "create EFI file system on second disk"
	mkdosfs -F 32 -s 1 -n EFI ${DISK2}p1

	echo "remove /boot/grub from fstab"
	sed -i '/grub/d' /etc/fstab

	echo "umount /boot/grub"
	umount /boot/grub

	# TODO: Verify with df -h, /boot should be mounted on bpool/BOOT/ubuntu_UID, /boot/efi on /dev/sda1 or similar depending on device name of your first disk, and no /boot/grub

	echo "remove /boot/grub"
	rm -rf /boot/grub

	echo "create ZFS datatset for grub"
	zfs create -o com.ubuntu.zsys:bootfs=no bpool/grub

	echo "refresh initrd files"
	update-initramfs -c -k all

	echo "disable memory zeroing to address a performance regression of ZFS on linux"
	sed -i.bak "s/GRUB_CMDLINE_LINUX_DEFAULT=\"quiet splash\"/GRUB_CMDLINE_LINUX_DEFAULT=\"quiet splash init_on_alloc=0\"/g" /etc/default/grub

	echo "update grub"
	update-grub

	echo "reload daemon"
	systemctl daemon-reload

	echo "install grub to the esp"
	grub-install --target=x86_64-efi --efi-directory=/boot/efi --bootloader-id=ubuntu --recheck --no-floppy

	echo "disable grub-initrd-fallback.service"
	systemctl mask grub-initrd-fallback.service

	echo "DONE without errors"

	dpkg-reconfigure grub-efi-amd64