--- zfs	2016-10-13 08:19:54.000000000 +0200
+++ zfs	2019-05-21 11:25:16.949181000 +0200
@@ -16,6 +16,11 @@ 
 stop_cmd="zfs_stop"
 required_modules="zfs"
 
+# Add the following lines to /etc/rc.conf to enable ZFS ordered mount:
+# zfs_ordered_mount_enable (bool):  Mount ZFS in order (or NO).
+
+zfs_ordered_mount_enable=${zfs_ordered_mount_enable:-"NO"}
+
 zfs_start_jail()
 {
 	if [ `$SYSCTL_N security.jail.mount_allowed` -eq 1 ]; then
@@ -25,11 +30,38 @@ 
 
 zfs_start_main()
 {
-	zfs mount -va
+	if checkyesno zfs_ordered_mount_enable; then
+		local _zroot _zpool
+
+		_zroot=`df -t zfs / | tail -1 | cut -d / -f 1`
+
+		if [ -n "${_zroot}" ]; then
+			zfs_mount_pool ${_zroot}
+		fi
+
+		for _zpool in `zpool list -Ho name`; do
+			if [ "${_zpool}" != "${_zroot}" ]; then
+				zfs_mount_pool ${_zpool}
+			fi
+		done
+	else
+		zfs mount -va
+	fi
 	zfs share -a
 	if [ ! -r /etc/zfs/exports ]; then
 		touch /etc/zfs/exports
 	fi
+}
+
+zfs_mount_pool()
+{
+	local _fs1 _fs2
+
+	_fs1=`zfs list -Hro mountpoint,name -t filesystem ${1} | egrep -ve '^legacy|^none' | awk '{print $2}'`
+
+	for _fs2 in `zfs list -Hro canmount,name -t filesystem ${_fs1} | egrep -ve ^off | awk '{print $2}'`; do
+		zfs mount -v ${_fs2}
+	done
 }
 
 zfs_start()