diff --git a/catcli/catcli.py b/catcli/catcli.py
index 7aa6a98..9f41c9c 100755
--- a/catcli/catcli.py
+++ b/catcli/catcli.py
@@ -37,7 +37,7 @@ USAGE = """
 
 Usage:
     {1} index  [--catalog=<path>] [--meta=<meta>...] [-acfnV] <name> <path>
-    {1} update [--catalog=<path>] [-acfnV] <name> <path>
+    {1} update [--catalog=<path>] [-acfnV] [--lpath=<path>] <name> <path>
     {1} ls     [--catalog=<path>] [-arVS] [<path>]
     {1} find   [--catalog=<path>] [-abdVP] [--path=<path>] <term>
     {1} rm     [--catalog=<path>] [-fV] <storage>
@@ -50,21 +50,22 @@ Usage:
     {1} --version
 
 Options:
-    --catalog=<path>  Path to the catalog [default: {2}].
-    --meta=<meta>     Additional attribute to store [default: ].
-    -p --path=<path>  Start path.
-    -n --no-subsize   Do not store size of directories [default: False].
-    -a --archive      Handle archive file [default: False].
-    -f --force        Do not ask when updating the catalog [default: False].
-    -d --directory    Only directory (default: False).
-    -b --script       Output script to manage found file(s) [default: False].
-    -S --sortsize     Sort by size, largest first [default: False].
-    -c --hash         Calculate md5 hash [default: False].
-    -r --recursive    Recursive [default: False].
-    -P --parent       Ignore stored relpath [default: True].
-    -V --verbose      Be verbose [default: False].
-    -v --version      Show version.
-    -h --help         Show this screen.
+    --catalog=<path>    Path to the catalog [default: {2}].
+    --meta=<meta>       Additional attribute to store [default: ].
+    -p --path=<path>    Start path.
+    -l --lpath=<path>   Path where changes are logged [default: ]
+    -n --no-subsize     Do not store size of directories [default: False].
+    -a --archive        Handle archive file [default: False].
+    -f --force          Do not ask when updating the catalog [default: False].
+    -d --directory      Only directory (default: False).
+    -b --script         Output script to manage found file(s) [default: False].
+    -S --sortsize       Sort by size, largest first [default: False].
+    -c --hash           Calculate md5 hash [default: False].
+    -r --recursive      Recursive [default: False].
+    -P --parent         Ignore stored relpath [default: True].
+    -V --verbose        Be verbose [default: False].
+    -v --version        Show version.
+    -h --help           Show this screen.
 """.format(BANNER, NAME, CATALOGPATH)
 
 
@@ -103,6 +104,7 @@ def cmd_update(args, noder, catalog, top, debug=False):
     path = args['<path>']
     name = args['<name>']
     hash = args['--hash']
+    logpath = args['--lpath']
     subsize = not args['--no-subsize']
     if not os.path.exists(path):
         Logger.err('\"{}\" does not exist'.format(path))
@@ -112,7 +114,8 @@ def cmd_update(args, noder, catalog, top, debug=False):
         Logger.err('storage named \"{}\" does not exist'.format(name))
         return
     start = datetime.datetime.now()
-    walker = Walker(noder, hash=hash, debug=debug)
+    walker = Walker(noder, hash=hash, debug=debug,
+                    logpath=logpath)
     cnt = walker.reindex(path, root, top)
     if subsize:
         noder.rec_size(root)
diff --git a/catcli/logger.py b/catcli/logger.py
index a056d01..64ded23 100644
--- a/catcli/logger.py
+++ b/catcli/logger.py
@@ -96,3 +96,10 @@ class Logger:
     def bold(string):
         '''make it bold'''
         return '{}{}{}'.format(Logger.BOLD, string, Logger.RESET)
+
+    def flog(path, string, append=True):
+        mode = 'w'
+        if append:
+            mode = 'a'
+        with open(path, mode) as f:
+            f.write(string)
diff --git a/catcli/walker.py b/catcli/walker.py
index 45f0bad..ebc6fbb 100644
--- a/catcli/walker.py
+++ b/catcli/walker.py
@@ -15,16 +15,19 @@ class Walker:
 
     MAXLINE = 80 - 15
 
-    def __init__(self, noder, hash=True, debug=False):
+    def __init__(self, noder, hash=True, debug=False,
+                 logpath=None):
         '''
         @noder: the noder to use
         @hash: calculate hash of nodes
         @debug: debug mode
+        @logpath: path where to log catalog changes on reindex
         '''
         self.noder = noder
         self.hash = hash
         self.noder.set_hashing(self.hash)
         self.debug = debug
+        self.lpath = logpath
 
     def index(self, path, parent, name, storagepath=''):
         '''index a directory and store in tree'''
@@ -83,7 +86,7 @@ class Walker:
                     self._debug('\tskip file {}'.format(sub))
                     self.noder.flag(n)
                     continue
-                Logger.out('- update catalag for \"{}\"'.format(sub))
+                self._log2file('update catalog for \"{}\"'.format(sub))
                 n = self.noder.file_node(os.path.basename(f), sub,
                                          parent, storagepath)
                 self.noder.flag(n)
@@ -95,7 +98,7 @@ class Walker:
                 treepath = os.path.join(storagepath, d)
                 reindex, dummy = self._need_reindex(parent, sub, treepath)
                 if reindex:
-                    Logger.out('- update catalog for \"{}\"'.format(sub))
+                    self._log2file('update catalog for \"{}\"'.format(sub))
                     dummy = self.noder.dir_node(base, sub, parent, storagepath)
                     cnt += 1
                 self.noder.flag(dummy)
@@ -147,3 +150,10 @@ class Walker:
         if len(string) > self.MAXLINE:
             string = string[:self.MAXLINE] + '...'
         Logger.progr('indexing: {:80}'.format(string))
+
+    def _log2file(self, string):
+        '''log to file'''
+        if not self.lpath:
+            return
+        line = '{}\n'.format(string)
+        Logger.flog(self.lpath, line, append=True)
diff --git a/tests/test_update.py b/tests/test_update.py
index c881862..7bcdb66 100644
--- a/tests/test_update.py
+++ b/tests/test_update.py
@@ -60,7 +60,8 @@ class TestIndexing(unittest.TestCase):
         tmpdirname = 'tmpdir'
         args = {'<path>': dirpath, '<name>': tmpdirname,
                 '--hash': True, '--meta': ['some meta'],
-                '--no-subsize': False, '--verbose': True}
+                '--no-subsize': False, '--verbose': True,
+                '--lpath': None}
 
         # index the directory
         unix_tree(dirpath)