Recently a friend asked about Installing Percona Monitoring Tools for Nagios as he was facing a few issues. I managed to set-it-up on my ubuntu VM. Sharing the the work-log of Nagios and Percona Monitoring Plugins setup steps here for some-one who’s looking for the same!

Install Nagios on Ubuntu – steps:

(skip to Percona Monitoring Tools – Nagios Plugin Setup)

Install dependencies:

sudo apt-get install build-essential libgd2-xpm-dev apache2-utils libssl-dev

Configure Nagios users & group:

sudo useradd -m nagios
sudo passwd nagios
sudo groupadd nagcmd
sudo usermod -a -G nagcmd nagios
sudo usermod -a -G nagcmd www-data

Download nagios setup and plugins:

wget http://prdownloads.sourceforge.net/sourceforge/nagios/nagios-4.0.8.tar.gz
wget http://nagios-plugins.org/download/nagios-plugins-2.0.3.tar.gz

Install Nagios:

tar xzf nagios-4.0.8.tar.gz
cd nagios-4.0.8
sudo ./configure --with-command-group=nagcmd
sudo make all
sudo make install
sudo make install-init
sudo make install-config
sudo make install-commandmode

sudo /usr/bin/install -c -m 644 sample-config/httpd.conf /etc/apache2/sites-enabled/nagios.conf

sudo htpasswd -c /usr/local/nagios/etc/htpasswd.users nagiosadmin
sudo service apache2 restart

Install Nagios Plugins:

tar xzf nagios-plugins-2.0.3.tar.gz
cd nagios-plugins-2.0.3
sudo ./configure --with-nagios-user=nagios --with-nagios-group=nagios
sudo make
sudo make install

Installing & configuring NRPE

$] wget http://garr.dl.sourceforge.net/project/nagios/nrpe-2.x/nrpe-2.15/nrpe-2.15.tar.gz
$] tar xzf nrpe-2.15.tar.gz
$] cd nrpe-2.15

Compile and install the NRPE addon.
$] ./configure

You may face following error:
	"checking for SSL libraries... configure: error: Cannot find ssl libraries"

Try specifying ssl & lib path as follows:
$] ./configure --with-ssl=/usr/bin/openssl --with-ssl-lib=/usr/lib/i386-linux-gnu/

 General Options:
 -------------------------
 NRPE port:    5666
 NRPE user:    nagios
 NRPE group:   nagios
 Nagios user:  nagios
 Nagios group: nagios


Review the options above for accuracy.  If they look okay,
type 'make all' to compile the NRPE daemon and client.
...
...
...

$] make all
$] make install-plugin
$] make install-daemon
$] make install-daemon-config
$] make install-xinetd
$] service xinetd restart
$] vi  /etc/xinetd.d/nrpe
	# default: on
	# description: NRPE (Nagios Remote Plugin Executor)
	service nrpe
	{
		flags           = REUSE
		socket_type     = stream
		port            = 5666
		wait            = no
		user            = nagios
		group           = nagios
		server          = /usr/local/nagios/bin/nrpe
		server_args     = -c /usr/local/nagios/etc/nrpe.cfg --inetd
		log_on_failure  += USERID
		disable         = no
		only_from       = 127.0.0.1 localhost
	}

$] vi /etc/services 
	nrpe            5666/tcp                 NRPE
$] service xinetd restart
$] netstat -at | grep nrpe
	tcp        0      0 *:nrpe                  *:*                     LISTEN     

Configure:

sudo vi /usr/local/nagios/etc/objects/contacts.cfg
define contact{
        contact_name                    nagiosadmin
        use                             generic-contact
        alias                           Nagios Admin;
        email                           your-email@your-domain.com;
}

sudo vi /etc/apache2/sites-enabled/nagios.conf
## Comment the following lines ##
#   Order allow,deny
#   Allow from all

## Uncomment and Change lines as shown below ##
Order deny,allow
Deny from all
Allow from 127.0.0.1 192.168.1.0/24

Enable Apache’s rewrite and cgi modules:

sudo a2enmod rewrite
sudo a2enmod cgi

#Restart apache service.
sudo service apache2 restart

Check nagios.conf file for any syntax errors and start nagios service:

sudo /usr/local/nagios/bin/nagios -v /usr/local/nagios/etc/nagios.cfg
sudo service nagios start

You should be able to view the nagios admin panel GUI through:
http//localhost/nagios/

Well so until now we did the basic Nagios installation & config, let us begin with main task…

Percona Nagios Plugins Installation and Configuration:

Navigate to Percana plugins download page: https://www.percona.com/downloads/percona-monitoring-plugins/

You can see the plugins directory by reviewing resources.cfg where we’re going to install the plugins:

vi /usr/local/nagios/etc/resource.cfg
	# Sets $USER1$ to be the path to the plugins
	$USER1$=/usr/local/nagios/libexec

Download and copy over the plugins to plugin directory:

cd /tmp
wget https://www.percona.com/downloads/percona-monitoring-plugins/1.1.5/percona-monitoring-plugins-1.1.5.tar.gz
tar -xzf percona-monitoring-plugins-1.1.5.tar.gz
cd percona-monitoring-plugins-1.1.5/nagios/bin
cp * /usr/local/nagios/libexec/

Configuration for Percona plugins for Nagios:
(I’ve copied over all though you might not need all of them!
Also not that commands like ‘check_mysql_deadlocks’ reads percona.deadlocks table created by pt-deadlock-logger.)

Define commands:

root@server3:/usr/local/nagios/etc/objects# vi commands.cfg

	define command{
		command_name    check_nrpe_service
		command_line    $USER1$/check_nrpe -H $HOSTADDRESS$
		}

	define command{
		command_name    check_mysql_service
		command_line    $USER1$/check_mysql -H $HOSTADDRESS$ --extra-opts=client@/etc/nagios/mysql.cnf
		}

	define command{
		command_name    check_nrpe
		command_line    $USER1$/check_nrpe -H $HOSTADDRESS$ -c $ARG1$
		}

	define command{
		command_name    check_mysql_connections
		command_line    $USER1$/pmp-check-mysql-status -H $HOSTADDRESS$ -x Threads_connected -o / -y max_connections -T pct -w 80 -c 95
		}

	define command{
		command_name    check_mysql_active_threads
		command_line    $USER1$/pmp-check-mysql-status -H $HOSTADDRESS$ -x Threads_running -w $ARG1$ -c $ARG2$
		}

	define command{
		command_name    check_mysql_processlist
		command_line    $USER1$/pmp-check-mysql-processlist -H $HOSTADDRESS$ -C $ARG1$ -w $ARG2$ -c $ARG3$
		}

	define command {
		command_name    check_mysql_innodb
		command_line    $USER1$/pmp-check-mysql-innodb -H $HOSTADDRESS$ -C $ARG1$ -w $ARG2$ -c $ARG3$
		}

	define command{
		command_name    check_mysql_replication_delay
		command_line    $USER1$/pmp-check-mysql-replication-delay -H $HOSTADDRESS$ -w $ARG1$ -c $ARG2$
		}

	define command{
		command_name    check_mysql_replication_running
		command_line    $USER1$/pmp-check-mysql-replication-running -H $HOSTADDRESS$
		}

	define command{
		command_name    check_mysql_deadlocks
		command_line    $USER1$/pmp-check-mysql-deadlocks -H $HOSTADDRESS$ -i 5 -w 12 -c 60
		}

	define command{
		command_name    check_mysql_table_checksum
		command_line    $USER1$/pmp-check-pt-table-checksum -H $HOSTADDRESS$
		}

Define hosts, host-groups and services:

root@server3:/usr/local/nagios/etc/objects# vi localhost.cfg 

# Hosts / hostgroups

	define host{
		use                     linux-server
		host_name               localhost
		alias                   localhost
		address                 127.0.0.1
        }

	define hostgroup{
		hostgroup_name mysql-servers
		alias MySQL Servers
		members localhost
	}

	define hostgroup{
		hostgroup_name mysql-masters
		alias MySQL Servers
		members localhost
	}

	define hostgroup{
		hostgroup_name mysql-slaves
		alias MySQL Servers
		members localhost
	}

# Services:

	define service{
		use                             active-service
		hostgroup_name                  mysql-servers
		service_description             NRPE Service
		check_command                   check_nrpe_service
		}

	define service{
		use                             active-service
		hostgroup_name                  mysql-servers
		service_description             MySQL Service
		check_command                   check_mysql_service
		}

	define service{
		use                             active-service
		hostgroup_name                  mysql-servers
		service_description             Free Memory
		check_command                   check_nrpe!rdba_unix_memory
		}

	define service{
		use                             active-service
		hostgroup_name                  mysql-servers
		service_description             MySQL PID
		check_command                   check_nrpe!rdba_mysql_pidfile
		}

	define service{
		use                             active-service
		hostgroup_name                  mysql-servers
		service_description             MySQL Processlist
		check_command                   check_mysql_processlist!states_count!16!32
		}

	define service{
		use                             active-service
		hostgroup_name                  mysql-servers
		service_description             MySQL User Connections 
		check_command                   check_mysql_processlist!max_user_conn!90!95
		}

	define service{
		use                             active-service
		hostgroup_name                  mysql-servers
		service_description             MySQL Connections
		check_command                   check_mysql_connections
		}

	define service{
		use                             active-service
		hostgroup_name                  mysql-servers
		service_description             MySQL Active Threads
		check_command                   check_mysql_active_threads!40!400
		}

	define service{
		use                             active-service
		hostgroup_name                  mysql-servers
		service_description             MySQL InnoDB Idle Blocker
		check_command                   check_mysql_innodb!idle_blocker_duration!60!600
		}

	define service{
		use                             active-service
		hostgroup_name                  mysql-servers
		service_description             MySQL InnoDB Long Transaction 
		check_command                   check_mysql_innodb!max_duration!86400!172800
		}

	define service{
		use                             active-service
		hostgroup_name                  mysql-servers
		service_description             MySQL InnoDB Lock Waits 
		check_command                   check_mysql_innodb!waiter_count!10!25
		}

	define service{
		use                             active-service
		hostgroup_name                  mysql-servers
		service_description             MySQL Replication Running
		check_command                   check_mysql_replication_running
		}

	define service{
		use                             active-service
		hostgroup_name                  mysql-servers
		service_description             MySQL Replication Delay
		check_command                   check_mysql_replication_delay!300!600
		}

	define service{
		use                             active-service
		hostgroup_name                  mysql-masters
		service_description             MySQL Deadlocks
		check_command                   check_mysql_deadlocks
		}
		
	define service{
		use                             active-service
		hostgroup_name                  mysql-slaves
		service_description             MySQL Table Checksums
		check_command                   check_mysql_table_checksum
		}

Create database user:

GRANT USAGE, SELECT, REPLICATION CLIENT on *.* to 'nagios'@'localhost' IDENTIFIED BY 'nagios';

Add the database user in configuration for nagios to access:

vi /etc/nagios/my.cnf
	[client]
	user=nagios
	password=nagios

– Restart Nagios and review the nagios admin panel:

/etc/init.d/nagios restart

Nagios Dashboard:

Hope this helps.

Update:
Hope you have not missed “Effective MySQL Monitoring” Video from Baron (Percona):

References:
https://www.percona.com/doc/percona-monitoring-plugins/1.1/
https://www.percona.com/doc/percona-monitoring-plugins/1.1/_downloads/config-example.txt