ansible-nagios

This is a playbook for installing and setting up the Nagios monitoring server and clients on CentOS, Rocky, RHEL, Fedora, and FreeBSD.

What does it do?

• Automatically installs Nagios Server on CentOS7, Rocky 8/9, or RHEL 7/8/9.
• Installs the Nagios client on various systems like CentOS, RHEL, Rocky, Fedora, and FreeBSD.
  • Creates service checks based on your hosts listed in Ansible inventory.
  • Sets up checks for the Nagios server itself.
  • Monitors all hosts/services via NRPE.
  • Uses jinja2 templates for most configurations.
  • Wraps Nagios in SSL using Apache.
  • Configures firewall rules.
  • Sends alerts via email and webhooks.
  • Available on Ansible Galaxy.

How do I use it?

• Specify your Nagios server in the [nagios] section of the hosts inventory.
• Add respective services and hosts in their inventory group; remember, a host can belong to only one group.
• Modify settings like email addresses and users in install/group_vars/all.yml.
• Run the playbook described below.

Requirements

• Nagios server needs CentOS7 or RHEL7/8/9 or Rocky 8/9.
• For the NRPE client, use RHEL6/7/8/9, CentOS6/7/8/9, Fedora, or FreeBSD.
• For SuperMicro monitoring via IPMI (optional):
  • Install perl-IPC-Run and perl-IO-Tty RPMs for RHEL7.
  • Update install/group_vars/all.yml to set supermicro_enable_checks: true.
• IPMI sensor monitoring might be removed due to reliability issues; SNMP is better.

Notes

• The default nagiosadmin password is changeme; change it to something secure.
• A read-only user is created, set nagios_create_guest_user: false to disable this.
• Adjust firewall rules management via install/group_vars/all.yml.
• Adding new hosts regenerates the Nagios configs.

Supported Service Checks

• Easy implementation with checks for:
  • Basic interfaces (ping, ssh, http).
  • Linux server health (load, users, uptime, disk space).
  • ELK servers, webservers (with SSL checks), DNS servers.
  • Jenkins and FreeNAS checks.
  • IoT devices, network switches, and Dell iDRAC health checks.
• Notification settings are in install/group_vars/all.yml.

Nagios Server Instructions

• Clone the repo and set up your Ansible inventory file:

git clone https://github.com/sadsfae/ansible-nagios
cd ansible-nagios
sed -i 's/host-01/yournagioshost/' hosts

• Add hosts for monitoring in the hosts inventory.
• Ensure hosts belong to only one category.
• For special hosts (like IDRAC), provide only IP addresses.
• For others, use FQDN.

Run the playbook:

ansible-playbook -i hosts install/nagios.yml

• Access the server via https://yourhost/nagios.
• Default login is nagiosadmin / changeme.

Known Issues

• For non-root users, you'll need to set ansible_system_user: ec2-user in install/group_vars/all.yml.
• SELinux might cause issues; if Nagios doesn't start, create an SELinux policy module:

# cat /var/log/audit/audit.log | audit2allow -M mynagios
# semodule -i mynagios.pp

Then restart Nagios and Apache:

systemctl restart nagios
systemctl restart httpd

If needed, switch SELinux to permissive until it's working:

setenforce 1

• For RHEL7 errors, install extra Perl packages if using SuperMicro monitoring.

Mass-generating Ansible Inventory

If managing with QUADS, generate iDRAC or OOB interfaces with:

quads-cli --ls-hosts | sed -e 's/^/mgmt-/g' > /tmp/all_ipmi_2019-10-23
for ipmi in $(cat all_ipmi_2019-10-23); do printf $ipmi ; echo " ansible_host=$(host $ipmi | awk '{print $NF}')"; done > /tmp/add_oobserver

Paste /tmp/add_oobserver into your Ansible inventory.

Demonstration

Watch a video demonstration of the deployment here:

iDRAC Server Health Details

Choose which iDRAC health checks to monitor, with detailed health information provided.

Files Overview

.
├── hosts
├── install
│   ├── group_vars
│   │   └── all.yml
│   ├── nagios.yml
│   └── roles
│       ├── firewall
│       │   └── tasks
│       │       └── main.yml
│       ├── firewall_client
│       │   └── tasks
│       │       └── main.yml
│       ├── instructions
│       │   └── tasks
│       │       └── main.yml
│       ├── nagios
│       │   ├── files
│       │   ├── handlers
│       │   ├── tasks
│       │   └── templates
│       └── nagios_client
│           ├── files
│           ├── handlers
│           ├── tasks
│           └── templates
├── meta
│   └── main.yml
└── tests
    └── test-requirements.txt

Total: 21 directories, 43 files.