Category: Nagios

Change email address from which Nagios sends messages

In some cases you want to change default email address of anonymous@hostname from which Nagios sends notifications. This can easily be done by changing following directives in Nagios configuration files. 1. Open the main Nagios configuration file nagios.cfg and edit the line containing admin_email vim nagios.cfg admin_email=nagios@localhost # change to your desired smtp address 2.

CentsOS Upgrade Nagios to 4.3.4

We had NAGIOS installed from CentOS repositories version 4.x.x. But we upgraded nrpe to version 3 which did not support old NAGIOS version that comes with repository. This is how we upgraded to veriosn 4.3.4 yum install rsync wget rsync -rav /usr/local/nagios/ /opt/nagios411backup/ wget tar xf ./nagios-4.3.4.tar.gz && cd ./nagios-4.3.4 ./configure --with-command-group=nagcmd make all

Monitoring SMTP with Nagios

In this quick how to we will look at monitoring Publicly available SMTP servers with Nagios. We will be doing basic monitoring just to see weather server resopnds on port 25 within 10 seconds. We will be using plugin called check_smtp. Prerequisites: We already have Nagios up and running and will be monitoring two SMTP

Adding Nagios plugin to NRPE check

In this example we will add check_ntp_time plugin to nrpe checks. We already have fully functioning NAGIOS monitoring server and client running NRPE. We are runnign CentOS 7 on both Nagios server and client.

Install Nagios NRPE from source code on CentOS or Debian

In order to monitor internal resources of remote systems with Nagios you will need NRPE installed and configured on a client. There will be two pieces to install NRPE daemon and nrpe plugins. This particular install was tested with CentOS and Debian.

Monitoring websites with NAGIOS and custom python script

Nagios is excellent monitoring tool and python is very powerful scripting language. Lets take a look how we can put this 2 together to create our own website monitoring plug-in. We will monitor basic public http response via python httplib module. In our example NAGIOS is installed on CentOS 7, procedure should be the same