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+Nagios plugin to check Postgres Streaming replication
+=====================================================
+
+This script could be used as Nagios check plugin to verify Postgres Streaming
+replication state.
+
+This script :
+
+- check if Postgres is running (CRITICAL raise if not)
+- check if Postgres is in recovery mode :
+  - if Postgres is in recovery mode :
+    - retreive from Postgres the last xlog file receive and the xlog file replay
+    - check if Postgres recovery configuration file is NOT present (CRITICAL
+      raise if present)
+    - retreive master connection informations from Postgres recovery configuration
+      file (UNKNOWN raise on error). Default Postgres master TCP port will be used
+      if port is not specify.
+    - retreive  current xlog file from Postgres master server (UNKNOWN raise on error).
+    - check if the last receive xlog file is the last replay xlog file (WARNING raise if not)
+    - Return OK state
+- if Postgres is not in recovery mode :
+  - check if Postgres recovery configuration file is present (CRITICAL raise if present)
+  - check if stand-by client(s) is connected (WARNING raise if not)
+  - Return OK state with list and count of stand-by client(s)
+
+Requirements
+------------
+
+ * On master node :
+
+     Slaves node must be able to connect with user PG_USER to database postgres as trust.
+
+ * On standby node :
+
+     PG_USER must be able to connect localy as trust
+
+Usage
+-----
+
+    Usage : ./check_pg_streaming_replication [-h] [-d] [options]
+	-u pg_user		Specify Postgres user (Default : postgres)
+	-b psql_bin		Specify psql binary path (Default : /usr/bin/psql)
+	-m pg_main		Specify Postgres main directory path
+				(Default : /var/lib/postgresql/9.1/main)
+	-r recovery_conf	Specify Postgres recovery configuration file path
+				(Default : /var/lib/postgresql/9.1/main/recovery.conf)
+	-p pg_port		Specify default Postgres master TCP port (Default : 5432)
+	-d			Debug mode
+	-h 			Show this message
+
+Copyright
+---------
+
+Copyright (c) 2013 Benjamin Renard
+
+License
+-------
+
+This program is free software; you can redistribute it and/or
+modify it under the terms of the GNU General Public License version 2
+as published by the Free Software Foundation.
+
+This program is distributed in the hope that it will be useful,
+but WITHOUT ANY WARRANTY; without even the implied warranty of
+MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
+GNU General Public License for more details.
+
+You should have received a copy of the GNU General Public License
+along with this program; if not, write to the Free Software
+Foundation, Inc., 59 Temple Place - Suite 330, Boston, MA  02111-1307, USA.