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====== ZFS - Clone a system - Detailed Instructions ======

===== Boot the target system =====

Boot the target system that will receive the ZFS Snapshot.

----

===== Remove all previous snapshots on the target system =====

<code bash>
zpool import -f tank
zfs destroy -Rv 'tank@%'
</code>

----

===== Create a snapshot on the source system =====

On the source system, create a new snapshot, and send it to the target.

<code bash>
zfs snapshot -r 'tank@p1snap'
zfs send -v --props --replicate --large-block --compressed tank@p1snap | ssh root@target 'zfs receive -F tank'
</code>

----

===== Mount the received tank on the target system =====

On the target:

<code bash>
zfs set mountpoint=/sysroot tank/root
zfs set mountpoint=/sysroot/boot tank/root/boot
zfs set mountpoint=/sysroot/tmp tank/root/tmp
zfs set mountpoint=/sysroot/var tank/root/var
zfs mount -a
mount --rbind /dev/ /sysroot/dev/
mount --rbind /proc/ /sysroot/proc/
mount --rbind /sys/ /sysroot/sys/
mount --rbind /run/ /sysroot/run/
chroot /sysroot/ /bin/bash
</code>

<WRAP info>
**NOTE:**  This mounts the freshly received tank, and chroots into it.
</WRAP>

----

===== SELinux relabel =====

Sets the system to do an SELinux relabel:

<code bash>
touch /.autorelabel
</code>

----

===== Update /etc/fstab =====

Edit /etc/fstab, and fix any UUIDs:

<file bash /etc/fstab>
UUID="ABCD-E123"     /boot/efi  vfat  defaults                          0  0
</file>

----

===== Update hostname =====

Correct the hostname on the target:

<code bash>
echo some_hostname > /etc/hostname
</code>

----

===== Limit Memory Usage (Optional) =====

If the system receiving the clone is low spec, add the zfs configuration limiting memory usage:

<code bash>
cp /root/tiny-modprobe.d-zfs.conf /etc/modprobe.d/zfs.conf
</code>

----

===== Rebuild boot =====

<code bash>
dracut --force /boot/initramfs-5.2.9-200.fc30.x86_64.img 5.2.9-200.fc30.x86_64
ZPOOL_VDEV_NAME_PATH=YES grub2-mkconfig > /boot/grub2/grub.cfg
sed -i '/^set pager/ s/1/0/' /boot/grub2/grub.cfg
</code>

<WRAP info>
**NOTE:  This:

  * rebuilds the initial ram-filesystem.
  * rebuilds the grub.cfg.
  * disables the grub pager.

</WRAP>

----

===== Export the tank =====

On the target:

Exit the chroot, unmount filesystems, and export tank:

<code bash>
exit
umount -l /sysroot/{dev,proc,sys,run}/
zfs set mountpoint=/ tank/root
zfs set mountpoint=legacy tank/root/boot
zfs set mountpoint=legacy tank/root/tmp
zfs set mountpoint=legacy tank/root/var
zpool export tank
</code>

----

===== Reboot the Target =====

<code bash>
reboot -f
</code>

----

===== Remove the snapshot on the target =====

On the target, remove the snapshot p1snap:

<code bash>
zfs destroy -vr 'tank@p1snap'
</code>

----

===== Remove the snapshot on the source =====

On the sender, remove the snapshot p1snap:

<code bash>
zfs destroy -vr 'tank@p1snap'
</code>