How to do it...

1. Install the jxmlease Python package, as follows:

$ pip3 install jxmlease

2. Create a new playbook called pb_get_ospf_peers.yml and populate it with the following task to extract OSPF peering information:

---
- name: "Get OSPF Status"
  hosts: junos
  tasks:
    - name: "Get OSPF Neighbours Data"
      junos_command:
        commands: show ospf neighbor
        display: xml
      register: ospf_output

    - name: "Extract OSPF Neighbour Data"
      set_fact:
        ospf_peers: "{{ ospf_output.output[0]['rpc-reply']\
                        ['ospf-neighbor-information']['ospf-neighbor'] }}"

3. Update the pb_get_ospf_peers.yml playbook with the following task to validate that all OSPF peerings across all nodes are in a Full state:

    - name: "Validate All OSPF Peers are in Full State"
      assert:
        that: item['ospf-neighbor-state'] == 'Full'
        fail_msg: "Peer on Interface {{item['interface-name']}} is Down"
        success_msg: "Peer on Interface {{item['interface-name']}} is UP"
      loop: "{{ospf_peers}}"