--- a/scripts/pvlbackup-rsync-snapshot	Fri Mar 02 17:09:44 2012 +0200
+++ b/scripts/pvlbackup-rsync-snapshot	Fri Mar 02 17:16:16 2012 +0200
@@ -194,7 +194,11 @@
         # allow non-boolean values
         return value
 
-def config_int (name, value) :
+def config_int (name, value, default=False) :
+    if not value and default is not False:
+        # returning default value if one is given
+        return default
+
     try :
         return int(value)
 
@@ -250,7 +254,9 @@
     @classmethod
     def from_config (cls, options, name,
         format,
-        keep,
+
+        # deprecated
+        keep    = None,
     ) :
         if not format :
             # magic to use snapshot name
@@ -260,7 +266,7 @@
 
         return cls(name, 
             format  = _format, 
-            keep    = config_int('keep', keep),
+            keep    = config_int('keep', keep, default=None),
         )
 
     @classmethod
@@ -329,6 +335,9 @@
                 (option, config_bool(option, value, strict=False)) for option, value in rsync_options.iteritems()
             ])
 
+        if not intervals :
+            raise ConfigError("Missing required [target/{name}/intervals]".format(name=name))
+
         # lookup intervals
         _intervals = list(cls.config_intervals(name, intervals))
 
@@ -482,6 +491,10 @@
         # configured
         keep = interval.keep
 
+        if not keep :
+            log.info("%s: Zero keep given, not cleaning up anything", interval)
+            return
+
         # items to clean?
         items = os.listdir(dir_path)