--- a/sbin/ftjail	Tue Sep 06 09:40:05 2022 +0200
+++ b/sbin/ftjail	Thu Sep 08 09:43:31 2022 +0200
@@ -28,10 +28,10 @@
 
 COMMANDS:
 
-  datasets [OPTIONS] PARENT-BASE PARENT-SKELETON NAME
+  datasets-tmpl [OPTIONS] PARENT-BASE PARENT-SKELETON NAME
 
-    Create ZFS datasets for the ro base and the rw skeleton to be used
-    within for jails
+    Create the ZFS template datasets, i.e. the ro base and the rw
+    skeleton to be used within thin jails jails
 
     PARENT-BASE and PARENT-SKELETON must exist already and NAME must
     not exist.
@@ -75,16 +75,17 @@
 
 
 #
-# "datasets" -- create the ZFS dataset tree
+# "datasets-tmpl" -- create the ZFS dataset tree
 #
 # PARENT-BASE PARENT-SKELETON NAME
 #
-command_datasets() {
+command_datasets_tmpl() {
     # parent ZFS dataset -- child ZFS dataset name
     local _p_base _p_skel _name
     local _zfsopts
+    local _ds_base _ds_skel
 
-    _zfsopts="-u"
+    _zfsopts="-u -o canmount=noauto"
 
     _p_base="$1"
     _p_skel="$2"
@@ -98,17 +99,33 @@
         echo "ERROR: no parent dataset for skeleton given" >&2
         return 2
     fi
-    if [ -z "${_pname}" ]; then
+    if [ -z "${_name}" ]; then
         echo "ERROR: no name given" >&2
         return 2
     fi
 
-    _ds="${_pds}/${_cds}"
-    echo "Resulting new root dataset is \`${_ds}' at mountpoint \`${_pmp}/${_cds}'"
-    if zfs list -H -o mountpoint -t filesystem "${_ds}" >/dev/null 2>/dev/null; then
-        echo "ERROR: dataset \`${_ds}' does already exist" >&2
+    _ds_base="${_p_base}/${_name}"
+    _ds_skel="${_p_skel}/${_name}"    
+    echo "Resulting new root datasets:"
+    printf "\\t%s\\n" "${_ds_base}"
+    printf "\\t%s\\n" "${_ds_skel}"
+    if ! zfs list -H -o mountpoint -t filesystem "${_p_base}" >/dev/null 2>/dev/null; then
+        echo "ERROR: parent dataset \`${_p_base}' does not exist" >&2
         return 1
     fi
+    if zfs list -H -o mountpoint -t filesystem "${_ds_base}" >/dev/null 2>/dev/null; then
+        echo "ERROR: dataset \`${_ds_base}' does already exist" >&2
+        return 1
+    fi
+    if ! zfs list -H -o mountpoint -t filesystem "${_p_skel}" >/dev/null 2>/dev/null; then
+        echo "ERROR: parent dataset \`${_p_skel}' does not exist" >&2
+        return 1
+    fi
+    if zfs list -H -o mountpoint -t filesystem "${_ds_skel}" >/dev/null 2>/dev/null; then
+        echo "ERROR: dataset \`${_ds_skel}' does already exist" >&2
+        return 1
+    fi
+    return 0
 
     #
     # NOTE: For BEs these directory will be *excluded* from the BE
@@ -406,8 +423,8 @@
 shift
 
 case "${command}" in
-    datasets)
-        command_datasets "$@"
+    datasets-tmpl)
+        command_datasets_tmpl "$@"
         ;;
     populate)
         command_populate "$@"