run2000 / docker-nagios

Docker image for Nagios

Docker-Nagios

Docker image for Nagios

Nagios Core 4.5.3 running on Ubuntu 20.04 LTS with NagiosGraph, NRPE, NCPA, NSCA, and NRDP.

Product	Version
Nagios Core	4.5.3
Nagios Plugins	2.4.10
NRPE	4.1.0
NCPA	3.1.0
NSCA	2.10.2
NRDP	2.0.5

Configurations

• Nagios configuration lives in /opt/nagios/etc
  • Custom plugins live in /opt/nagios/custom-plugins
  • MIB files live in /opt/nagios/mibs
• NagiosGraph configuration lives in /opt/nagiosgraph/etc
• NRDP server configuration lives in /opt/nrdp/server

Install

Download the default image from Docker Hub by running:

docker pull run2000/nagios:latest

Alternatively, you can build the image from GitHub:

git clone https://github.com/run2000/Docker-Nagios.git 

cd Docker-Nagios
docker build -t nagios .

Additional build arguments may be passed into the Dockerfile at build time. The following sections describe these.

Operating System

This build argument specifies the Ubuntu base image on top of which the rest of the image is built. Change this at your own risk.

Build Arg	Default Value	Description
UBUNTU_VERSION	20.04	Ubuntu Focal LTS release image

Release versions

These build arguments configure the versions of each component that are fetched and installed.

Build Arg	Default Value	Description
NAGIOS_VER	4.5.3	The Nagios Core release version
NAGIOS_PLUGINS_VER	2.4.10	The Nagios Plugins release version
NRPE_VER	4.1.0	The NRPE release version
NCPA_VER	3.1.0	The NCPA release version
NSCA_VER	2.10.2	The NSCA release version
NRDP_VER	2.0.5	The NRDP release version

Default environment

These build arguments configure default Nagios behaviour. They can be overridden by environment variables when starting the container.

Build Arg	Default Value	Description
NAGIOS_FQDN	nagios.example.com	The server Fully Qualified Domain Name in Postfix
NAGIOS_TIMEZONE	UTC	The timezone of the server
NAGIOSADMIN_USER	nagiosadmin	The admin user name for the web interface
NAGIOSADMIN_PASS	nagios	The admin password for the web interface

NRDP configuration

These build arguments configure the default NRDP behaviour.

Build Arg	Default Value	Description
NRDP_ENABLED	1	Enable NRDP through the Apache 2 configuration.
NRDP_TOKEN		A token that may be used for NRDP requests.

NRDP may be disabled by setting NRDP_ENABLED to any other value.

If NRDP_TOKEN is unspecified, no tokens will be configured.

Running

Run with the example configuration with the following:

docker run --name nagios4 -p 0.0.0.0:8080:80 run2000/nagios:latest

alternatively you can use external Nagios configuration & log data with the following:

docker run --name nagios4  \
  -v /path-to-nagios/etc/:/opt/nagios/etc/ \
  -v /path-to-nagios/var:/opt/nagios/var/ \
  -v /path-to-custom-plugins:/opt/nagios/custom-plugins \
  -v /path-to-custom-mib-files:/opt/nagios/mibs \
  -v /path-to-nagiosgraph-var:/opt/nagiosgraph/var \
  -v /path-to-nagiosgraph-etc:/opt/nagiosgraph/etc \
  -v /path-to-nrdp-server:/opt/nrdp/server \
  -p 0.0.0.0:8080:80 run2000/nagios:latest

Note: The path for the custom plugins will be /opt/nagios/custom-plugins, you will need to reference this directory in your configuration scripts.

There are a number of environment variables that you can use to adjust the behaviour of the container:

Environment Variable	Description
MAIL_RELAY_HOST	Set Postfix relayhost
MAIL_INET_PROTOCOLS	Set the inet_protocols in Postfix
NAGIOS_FQDN	Set the server Fully Qualified Domain Name in Postfix
NAGIOS_TIMEZONE	Set the timezone of the server
NAGIOSADMIN_USER	Set the admin user name for the web interface
NAGIOSADMIN_PASS	Set the admin password for the web interface

For best results your Nagios image should have access to both IPv4 & IPv6 networks

Credentials

The default credentials for the web interface is nagiosadmin / nagios

To change this:

• Set the NAGIOSADMIN_USER and NAGIOSADMIN_PASS environment variables
• Update the /opt/nagios/etc/cgi.cfg file and update the authorized_for_* parameters to point add the new admin user
• Delete the /opt/nagios/etc/htpasswd.users file. This will be re-generated when the container is started.

Extra Plugins

• Nagiosgraph [http://exchange.nagios.org/directory/Addons/Graphing-and-Trending/nagiosgraph/details]
• Nagios Cross-Platform Agent (NCPA) [https://github.com/NagiosEnterprises/ncpa]
• Nagios Remote Plugin Executor (NRPE) [https://github.com/NagiosEnterprises/nrpe]
• Nagios Service Check Acceptor (NSCA) [https://github.com/NagiosEnterprises/nsca]
• Nagios Remote Data Processor (NRDP) [https://github.com/NagiosEnterprises/nrdp]

Credits

• This Docker image is based on the project at https://github.com/JasonRivers/Docker-Nagios
• Some improvements came from the project https://github.com/tronyx/Docker-Nagios

docker-nagios's Issues

Update base image to Ubuntu 22.04

Update the base image for the Docker image from 20.04 to 22.04.

So far the main sticking point is with OpenSSL 3.0. See NagiosEnterprises/nrpe#258 for possible fixes.

Remove workaround for SSL config in Nagios Core

SSL config needs to be disabled in Nagios Core 4.4.7 due to the update checks causing crashy behaviour, usually overnight.

This might be fixed by updating the Ubuntu base image to 22.04.

Meanwhile, disable SSL with configure:

./config --disable-ssl

See NagiosEnterprises/nagioscore#861 for the upstream bug report.

Update Nagios core to 4.4.7

See https://www.nagios.org/projects/nagios-core/history/4x/