18.2. Installing Nagios

The Nagios monitoring system is used to provide monitoring and alerts for the Red Hat Gluster Storage network and infrastructure. Installing Nagios installs the following components.
nagios
Core program, web interface and configuration files for Nagios server.
python-cpopen
Python package for creating sub-process in simple and safe manner.
python-argparse
Command line parser for python.
libmcrypt
Encryptions algorithm library.
rrdtool
Round Robin Database Tool to store and display time-series data.
pynag
Python modules and utilities for Nagios plugins and configuration.
check-mk
General purpose Nagios-plugin for retrieving data.
mod_python
An embedded Python interpreter for the Apache HTTP Server.
nrpe
Monitoring agent for Nagios.
nsca
Nagios service check acceptor.
nagios-plugins
Common monitoring plug-ins for nagios.
gluster-nagios-common
Common libraries, tools, configurations for Gluster node and Nagios server add-ons.
nagios-server-addons
Gluster node management add-ons for Nagios.

18.2.1. Installing Nagios Server

Use the following command to install Nagios server: 
# yum install nagios-server-addons
You must install Nagios on the node which would be used as the Nagios server.

18.2.2. Configuring Red Hat Gluster Storage Nodes for Nagios

Configure all the Red Hat Gluster Storage nodes, including the node on which the Nagios server is installed.

Note

If SELinux is configured, the sebooleans must be enabled on all Red Hat Gluster Storage nodes and the node on which Nagios server is installed.
Enable the following sebooleans on Red Hat Enterprise Linux node if Nagios server is installed. 
# setsebool -P logging_syslogd_run_nagios_plugins on
# setsebool -P nagios_run_sudo on
To configure the nodes, follow the steps given below:
  1. In /etc/nagios/nrpe.cfg file, add the central Nagios server IP address as shown below: 
    allowed_hosts=127.0.0.1, NagiosServer-HostName-or-IPaddress
  2. Restart the NRPE service using the following command: 
    # service nrpe restart

    Note

    • The host name of the node is used while configuring Nagios server using auto-discovery. To view the host name, run hostname command.
    • Ensure that the host names are unique.
  3. Start the glusterpmd service using the following command: 
    # service glusterpmd start
    To start glusterpmd service automatically when the system reboots, run chkconfig --add glusterpmd command.
    You can start the glusterpmd service using service glusterpmd start command and stop the service using service glusterpmd stop command.
    The glusterpmd service is a Red Hat Gluster Storage process monitoring service running in every Red Hat Gluster Storage node to monitor glusterd, self heal, smb, quotad, ctdbd and brick services and to alert the user when the services go down. The glusterpmd service sends its managing services detailed status to the Nagios server whenever there is a state change on any of its managing services.
    This service uses /etc/nagios/nagios_server.conf file to get the Nagios server name and the local host name given in the Nagios server. The nagios_server.conf is configured by auto-discovery.