[Bug]: Unable to assign primary mac address to vm interface when identical mac address exists

[bnerickson]

Ansible NetBox Collection version

v3.22.0

Ansible version

ansible [core 2.16.14]
  config file = /root/netbox_ansible_modules/ansible.cfg
  configured module search path = ['/root/.ansible/plugins/modules', '/usr/share/ansible/plugins/modules']
  ansible python module location = /usr/lib/python3.12/site-packages/ansible
  ansible collection location = /root/.ansible/collections:/usr/share/ansible/collections
  executable location = /bin/ansible
  python version = 3.12.12 (main, Nov 14 2025, 00:00:00) [GCC 11.5.0 20240719 (Red Hat 11.5.0-11)] (/usr/bin/python3.12)
  jinja version = 3.1.6
  libyaml = False

NetBox version

v4.5.0

Python version

3.11

Steps to Reproduce

NOTE: This is copied almost verbatim from #1413 because it's exactly the same save that it affects vm interfaces opposed to device interfaces. I'm creating this issue to justify a PR to fix it.

Create two virtual interfaces. Create and assign two separate, identical MAC address on both virtual interfaces. Assign the MAC address as primary on both virtual interfaces (fails). This should be possible as they are actually two separate mac_address objects, each assigned to a different vm interface:

- name: Create MAC addresses
  delegate_to: localhost
  netbox.netbox.netbox_mac_address:
    netbox_url: "{{ netbox_url }}"
    netbox_token: "{{ netbox_token }}"
    data: 
      assigned_object:
        virtual_machine: test_vm
        name: "{{ item }}"
      mac_address: AA:BB:CC:DD:EE:FF
    query_params:
      - assigned_object
      - name
  loop:
    - Gig-E1
    - virtual1
  register: netbox_mac_address_result

- name: Set NIC's Primary MAC addresses
  delegate_to: localhost
  netbox.netbox.netbox_vm_interface:
    netbox_url: "{{ netbox_url }}"
    netbox_token: "{{ netbox_token }}"
    data:
      virtual_machine: test_vm
      name: "{{ item.item }}"
      primary_mac_address: AA:BB:CC:DD:EE:FF
  loop: "{{ netbox_mac_address_result.results }}"

Expected Behavior

MAC address object assigned to interface Gig-E1 on test_vm is set as primary_mac_address on interface Gig-E1. MAC address object assigned to interface virtual1 on test_vm is set as primary_mac_address on interface virtual1.

Observed Behavior

Attempt to assign MAC address as primary mac adress of an interface results in the error:

msg: More than one result returned for primary_mac_address 

Despite the fact that there is only one unique mac address defined on each interface. It only happens to be the same mac_address string for each of those interfaces.

I have tried passing the mac address object id as primary_mac_address:

- name: Set NIC's Primary MAC addresses
  delegate_to: localhost
  netbox.netbox.netbox_vm_interface:
    netbox_url: "{{ netbox_url }}"
    netbox_token: "{{ netbox_token }}"
    data:
      virtual_machine: test_vm
      name: "{{ item.item }}"
      primary_mac_address: 
        id: "{{ item.mac_address.id "}}
loop: "{{ netbox_mac_address_result.results }}"

But this results in the error:

msg: 'Could not resolve id of primary_mac_address: {''id'': ''1147''}'

Passing the full mac_address object as primary_mac_address yields the same error.

It seems that the primary_mac_address parameter only accepts an actual MAC address string but then searches for it without considering the assigned_object being the same as the device_interface where we try to set the primary_mac_address for.

[bnerickson]

Draft PR: #1508

[bnerickson]

New PR: #1510

[xocoru]

@bnerickson, I see another problem here: you assume that "assigned_object" exists at this stage.
But in fact, it might not exist, and netbox_vm_interface will create it with "state: present".

At least it happens for me. It forces me to run netbox_vm_interface two times. One without mac, then create mac and then assign mac as primary. But I still have an issue, when you check the MAC address through the UI, you don't see the related object. And you have to run netbox_mac_address with assigned_object again to fix it .... chicken-egg problem

[bnerickson]

@bnerickson, I see another problem here: you assume that "assigned_object" exists at this stage. But in fact, it might not exist, and netbox_vm_interface will create it with "state: present".

At least it happens for me. It forces me to run netbox_vm_interface two times. One without mac, then create mac and then assign mac as primary. But I still have an issue, when you check the MAC address through the UI, you don't see the related object. And you have to run netbox_mac_address with assigned_object again to fix it .... chicken-egg problem

Yeah, that's been an issue for both physical device interfaces and vm interfaces since the mac_address feature was added. Feel free to open a new issue to address it. The aforementioned PR #1510 has been merged which should resolve the issue at hand.

edit:

What I do is:

- name: Create virtual interfaces in netbox
  netbox.netbox.netbox_vm_interface:
    netbox_url: "https://{{ netbox_server }}"
    netbox_token: "{{ netbox_api_token }}"
    state: present
    data:
      description: "{{ item.ifname }}"
      enabled: "{% if 'UP' in item.flags %}true{% else %}false{% endif %}"
      mtu: "{{ item.mtu }}"
      name: "{{ item.ifname }}"
      virtual_machine: "{{ ansible_fqdn }}"

- name: Create virtual interface mac addresses in netbox
  netbox.netbox.netbox_mac_address:
    netbox_url: "https://{{ netbox_server }}"
    netbox_token: "{{ netbox_api_token }}"
    state: present
    data:
      mac_address: "{{ item.address | upper }}"
      assigned_object:
        virtual_machine: "{{ ansible_fqdn }}"
        name: "{{ item.ifname }}"
    query_params:
      - assigned_object
      - name

- name: Update virtual interfaces in netbox (mac_address/primary_mac_address)
  netbox.netbox.netbox_vm_interface:
    netbox_url: "https://{{ netbox_server }}"
    netbox_token: "{{ netbox_api_token }}"
    state: present
    data:
      virtual_machine: "{{ ansible_fqdn }}"
      name: "{{ item.ifname }}"
      mac_address: "{{ item.address | upper }}"
      primary_mac_address:
        id: "{{ physical_mac_results.mac_address.id }}"