Now, the daemon will check that a base directory is NOT reached via

[rrdtool.git] / doc / rrdcached.pod

diff --git a/doc/rrdcached.pod b/doc/rrdcached.pod
index 4bd1bb8..d8f0c73 100644 (file)
--- a/doc/rrdcached.pod
+++ b/doc/rrdcached.pod
@@ -125,6 +125,18 @@ used.
   updated by the daemon,  assuming the base directory
   "/tmp".
 
+B<WARNING:> The paths up to and including the base directory B<MUST NOT BE>
+symbolic links.  In other words, if the base directory is
+specified as:
+
+    -b /base/dir/somewhere
+
+... then B<NONE> of the following should be symbolic links:
+
+    /base
+    /base/dir
+    /base/dir/somewhere
+
 =item B<-B>
 
 Only permit writes into the base directory specified in B<-b> (and any
@@ -173,7 +185,7 @@ The daemon reports errors in one of two ways: During startup, error messages
 are printed to C<STDERR>. One of the steps when starting up is to fork to the
 background and closing C<STDERR> - after this writing directly to the user is
 no longer possible. Once this has happened, the daemon will send log messages
-to the system logging daemon using L<syslog(3)>. The facility used it
+to the system logging daemon using L<syslog(3)>. The facility used is
 C<LOG_DAEMON>.
 
 =head1 HOW IT WORKS
@@ -363,6 +375,15 @@ sent B<after> the node has been dequeued.
 Causes the daemon to start flushing ALL pending values to disk.  This
 returns immediately, even though the writes may take a long time.
 
+=item B<PENDING> I<filename>
+
+Shows any "pending" updates for a file, in order.  The updates shown have
+not yet been written to the underlying RRD file.
+
+=item B<FORGET> I<filename>
+
+Removes I<filename> from the cache.  Any pending updates B<WILL BE LOST>.
+
 =item B<HELP> [I<command>]
 
 Returns a short usage message. If no command is given, or I<command> is
@@ -400,6 +421,10 @@ Adds more data to a filename. This is B<the> operation the daemon was designed
 for, so describing the mechanism again is unnecessary. Read L<HOW IT WORKS>
 above for a detailed explanation.
 
+Note that rrdcached only accepts absolute timestamps in the update values.
+Updates strings like "N:1:2:3" are automatically converted to absolute
+time by the RRD client library before sending to rrdcached.
+
 =item B<WROTE> I<filename>
 
 This command is written to the journal after a file is successfully
@@ -425,8 +450,8 @@ message itself.  The first user command after B<BATCH> is command number one.
 
     client:  BATCH
     server:  0 Go ahead.  End with dot '.' on its own line.
-    client:  UPDATE x.rrd N:1:2:3            <--- command #1
-    client:  UPDATE y.rrd N:3:4:5            <--- command #2
+    client:  UPDATE x.rrd 1223661439:1:2:3            <--- command #1
+    client:  UPDATE y.rrd 1223661440:3:4:5            <--- command #2
     client:  and so on...
     client:  .
     server:  2 Errors
@@ -460,10 +485,11 @@ daemon was started.
 
 =item B<DataSetsWritten> I<(unsigned 64bit integer)>
 
-Total number of "data sets" written to disk since the daemon was started. A
-data set is one or more values passed to the B<UPDATE> command. For example:
-C<N:123:456> is one data set with two values. The term "data set" is used to
-prevent confusion whether individual values or groups of values are counted.
+Total number of "data sets" written to disk since the daemon was
+started. A data set is one or more values passed to the B<UPDATE>
+command. For example: C<1223661439:123:456> is one data set with two
+values. The term "data set" is used to prevent confusion whether
+individual values or groups of values are counted.
 
 =item B<TreeNodesNumber> I<(unsigned 64bit integer)>