corregido error en flujo de control e informacion

cambio comparacion -n por -z, el -n no verifica la asignacion de la variable
añado puntos suspensitos para dar sensacion de trabajo

zonebackuptozone.sh

@@ -56,7 +56,7 @@ check_err()
 check_snap()
 {
     ZONE=$1
-    echo "Checking for snapshot of ${ZONE}"
+    echo "Checking for snapshot of ${ZONE}..."
     zfs list -t snapshot zones/${ZONE}@`date +%Y%m%d` 2>/dev/null 1>&2
 }
 
@@ -99,10 +99,11 @@ send_snap ${UUID}
 
 # we check this UUID for additional datasets
 
-echo "Look for addtional datasets"
+echo "Looking for addtional datasets in ${UUID}..."
 DATASET=`vmadm get ${UUID} | json datasets.0 | sed 's/zones\///' | tr -d '\n'`
+echo "done."
 
-if [ -n "${DATASET}" ]; then
+if [ -z "${DATASET}" ]; then
     check_snap ${DATASET}
 fi
 
@@ -110,7 +111,7 @@ if [ $? -ne 0 ]; then
     create_snap ${DATASET}
 else
     echo "Snapshot of ${DATASET} already available"
-    echo "done."
+    echo "Skipping create snapshot..."
 fi
 
 send_snap ${DATASET}