Minor doc additions for cascading replication.

doc/src/sgml/config.sgml

@@ -2095,7 +2095,7 @@ SET ENABLE_SEQSCAN TO OFF;
       to send replication data to one or more standby servers.
       Note that in addition to these parameters,
       <xref linkend="guc-wal-level"> must be set appropriately on the master
-      server, and may also want to enable WAL archiving as
+      server, and optionally WAL archiving can be enabled as
       well (see <xref linkend="runtime-config-wal-archiving">).
       The values of these parameters on standby servers are irrelevant,
       although you may wish to set them there in preparation for the

doc/src/sgml/monitoring.sgml

@@ -314,7 +314,8 @@ postgres: <replaceable>user</> <replaceable>database</> <replaceable>host</> <re
       The client's host name will be available only if
       <xref linkend="guc-log-hostname"> is set or if the user's host name
       needed to be looked up during <filename>pg_hba.conf</filename>
-      processing.
+      processing. Only directly connected standbys are listed; no information
+      about downstream standby servers is recorded.
      </entry>
      </row>