Netbox and Ansible for for Small to Mid Business Networks

Ansible and Netbox are not just for the high end data centre systems. They can also be used on networks using small to medium business switches and routers such as the Cisco SMB Product range.

Initial Auditing and OnBoarding

Initally I started with brand new empty Netbox. In which I manually created a base setup adding in each:

• Site
• Patch
• Device model in use
• Prefix, to begin with just the management subnets

Then creating a yaml file host listing to beging with, I ran an Ansible Playbook that then went through that list of devices pulling base device information:

• IP Address (Management)
• Hostname
• Model
• Serial number
• Firmware (This was not initally used)

This was then to record in to Netbox as new devices as well as exported to CSV. After I had the devices in Netbox I could do some base housekeeping and put them in the right sites, patches and rack locations.

Netbox, the Source of Truth

Once the devices were in and housekeeping done Netbox then became the Source of Truth for both our engineers and technicians and also for Ansible. I could remove the hosts yaml file an dpointing AQnsible at Netbox for its inventory I could now allow playbooks to be run against a site and other locations or across the whole group.

Minimum config

One of the frist tasks was to ensure I had all devices, configured to a standard. I hoped that they have been, but over time, without continued audits and checks, things can become a little out. So using Ansible I was able to ensure some defaults are set, such has:

• Disabling of access methods, such as HTTP, Telnet and also HTTPS
• NTP time servers and synchronised time
• Name Servers
• Monitoring service setting (SNMP)

Backup config

Another task for Ansible was to get regular configuration backups for all devices. Running an Ansible Playbook on a daily schedule (Cron) to pull the current configuration and store it on the local file system of the Ansible server. This was then replicated off site over secure protocols.

- name: Gather Facts
  gather_facts: no
  hosts: device_roles_switch
  vars:
    output_path: "{{ lookup('env', 'HOME') }}/backups/"

  tasks:
    ## Create backup folder for today
    - name: Get date stamp for filename creation
      set_fact: date="{{lookup('pipe','date +%Y%m%d')}}"
      run_once: true

    # Get Switch Config
    - name: Get Config
      community.ciscosmb.facts:
        gather_subset:
          - config

    - name: Save Config
      copy:
        content: "{{ ansible_net_config }}"
        dest: "{{ output_path }}{{ inventory_hostname }}-{{ date }}.txt"

Finding Trunks and Devices

Another task was find all the trunks between switches & patches and docuemnt them correctly in Netbox. Running an Ansible Playbook to use LLDP from gather facts to then determine th elinks between device, that could then be documented as Netbox cables. Once that was done I also used the Netbox Topology Views plugin to visualise the network.

Once that was done I could also use MAC address searches to determine what ports IP Phones, DAPs and WAPs were connected to among other devices. Since a standard brand of those was used throughout it was only a matter of searching for the manufacturer portion of the MAC address.