How to do it...

1. Create a new file called l3vpn.yml with the following content:

---
l3vpns:
  vpna:
    state: present
    rt: "target:{{bgp_asn}}:10"
    rd: "1:10"
    sites:
      - node: mxpe01
        port: ge-0/0/3.10
        ip: 172.10.1.1/24
     - node: mxpe02
       port: ge-0/0/3.10
       ip: 172.10.2.1/24
  vpnb:
    state: present
    rt: "target:{{bgp_asn}}:20"
    rd: "1:20"
    sites:
      - node: mxpe01
        port: ge-0/0/3.20
        ip: 172.20.1.1/24
      - node: mxpe02
        port: ge-0/0/3.20
        ip: 172.20.2.1/24

2. Create a new playbook called pb_junos_l3vpn.yml with the following tasks to configure the PE-Customer Edge (CE) links:

---
- name: "Deploy L3VPNs on Juniper Devices"
  hosts: pe
  vars_files:
    - "l3vpn.yml"
  tasks:
    - name: "Set VPN Interfaces"
      set_fact:
        l3vpn_intfs: "{{ l3vpn_intfs|default([]) +
          l3vpns[item.key].sites |
 selectattr('node','equalto',inventory_hostname) | list}}"
      with_dict: "{{l3vpns}}"
      delegate_to: localhost

    - name: "Configure Interfaces for L3VPN Sites"
      junos_config:
        lines:
          - set interfaces {{ item.port.split('.')[0]}} vlan-tagging
          - set interfaces {{ item.port}} vlan-id {{ item.port.split('.')[1] }}
      loop: "{{ l3vpn_intfs }}"

3. Add the following tasks in pb_junos_l3vpn.yml to set up the P2P IP address on the PE-CE links:

- name: "Configure IP address for L3VPN Interfaces"
  junos_l3_interface:
    name: "{{ item.port.split('.')[0]}}"
    ipv4: "{{ item.ip }}"
    unit: "{{ item.port.split('.')[1] }}"
  loop: "{{l3vpn_intfs}}"
  tags: intf_ip

4. Add the following task in pb_junos_l3vpn.yml to configure the virtual routings and forwardings (VRFs) on the PE nodes:

- name: "Configure L3VPNs"
  junos_vrf:
    name: "{{ item.key }}"
    rd: "{{item.value.rd}}"
    target: "{{ item.value.rt }}"
    interfaces: "{{ l3vpns[item.key].sites |
                    map(attribute='port') | list }}"
    state: "{{ item.value.state }}"
  with_dict: "{{l3vpns}}"
  when: inventory_hostname in (l3vpns[item.key].sites | map(attribute='node') | list)
  tags: l3vpn