+=head2 Plugin C<write_redis>
+
+The I<write_redis plugin> submits values to I<Redis>, a data structure server.
+
+Synopsis:
+
+ <Plugin "write_redis">
+ <Node "example">
+ Host "localhost"
+ Port "6379"
+ Timeout 1000
+ </Node>
+ </Plugin>
+
+Values are submitted to I<Sorted Sets>, using the metric name as the key, and
+the timestamp as the score. Retrieving a date range can then be done using the
+C<ZRANGEBYSCORE> I<Redis> command. Additionnally, all the identifiers of these
+I<Sorted Sets> are kept in a I<Set> called C<collectd/values> and can be
+retrieved using the C<SMEMBERS> I<Redis> command. See
+L<http://redis.io/commands#sorted_set> and L<http://redis.io/commands#set> for
+details.
+
+The information shown in the synopsis above is the I<default configuration>
+which is used by the plugin if no configuration is present.
+
+The plugin can send values to multiple instances of I<Redis> by specifying
+one B<Node> block for each instance. Within the B<Node> blocks, the following
+options are available:
+
+=over 4
+
+=item B<Node> I<Nodename>
+
+The B<Node> block identifies a new I<Redis> node, that is a new I<Redis>
+instance running in an specified host and port. The name for node is a
+canonical identifier which is used as I<plugin instance>. It is limited to
+64E<nbsp>characters in length.
+
+=item B<Host> I<Hostname>
+
+The B<Host> option is the hostname or IP-address where the I<Redis> instance is
+running on.
+
+=item B<Port> I<Port>
+
+The B<Port> option is the TCP port on which the Redis instance accepts
+connections. Either a service name of a port number may be given. Please note
+that numerical port numbers must be given as a string, too.
+
+=item B<Timeout> I<Milliseconds>
+
+The B<Timeout> option sets the socket connection timeout, in milliseconds.
+
+=back
+
+=head2 Plugin C<write_riemann>
+
+The I<write_riemann plugin> will send values to I<Riemann>, a powerfull stream
+aggregation and monitoring system. The plugin sends I<Protobuf> encoded data to
+I<Riemann> using UDP packets.
+
+Synopsis:
+
+ <Plugin "write_riemann">
+ <Node "example">
+ Host "localhost"
+ Port "5555"
+ Protocol UDP
+ StoreRates true
+ AlwaysAppendDS false
+ TTLFactor 2.0
+ </Node>
+ Tag "foobar"
+ </Plugin>
+
+The following options are understood by the I<write_riemann plugin>:
+
+=over 4
+
+=item E<lt>B<Node> I<Name>E<gt>
+
+The plugin's configuration consists of one or more B<Node> blocks. Each block
+is given a unique I<Name> and specifies one connection to an instance of
+I<Riemann>. Indise the B<Node> block, the following per-connection options are
+understood:
+
+=over 4
+
+=item B<Host> I<Address>
+
+Hostname or address to connect to. Defaults to C<localhost>.
+
+=item B<Port> I<Service>
+
+Service name or port number to connect to. Defaults to C<5555>.
+
+=item B<Protocol> B<UDP>|B<TCP>
+
+Specify the protocol to use when communicating with I<Riemann>. Defaults to
+B<UDP>.
+
+=item B<StoreRates> B<true>|B<false>
+
+If set to B<true> (the default), convert counter values to rates. If set to
+B<false> counter values are stored as is, i.e. as an increasing integer number.
+
+This will be reflected in the C<ds_type> tag: If B<StoreRates> is enabled,
+converted values will have "rate" appended to the data source type, e.g.
+C<ds_type:derive:rate>.
+
+=item B<AlwaysAppendDS> B<false>|B<true>
+
+If set the B<true>, append the name of the I<Data Source> (DS) to the
+"service", i.e. the field that, together with the "host" field, uniquely
+identifies a metric in I<Riemann>. If set to B<false> (the default), this is
+only done when there is more than one DS.
+
+=item B<TTLFactor> I<Factor>
+
+I<Riemann> events have a I<Time to Live> (TTL) which specifies how long each
+event is considered active. I<collectd> populates this field based on the
+metrics interval setting. This setting controls the factor with which the
+interval is multiplied to set the TTL. The default value is B<2.0>. Unless you
+know exactly what you're doing, you should only increase this setting from its
+default value.
+
+=back
+
+=item B<Tag> I<String>
+
+Add the given string as an additional tag to the metric being sent to
+I<Riemann>.
+
+=back
+