Configuring LDP
The example below creates an Ansible playbook to configure the LDP protocol.
ocnos_ldp.j2
First create a template for the LDP configuration:
osboxes@osboxes:~/playbooks$ cat templates/ocnos_ldp.j2
router ldp
{% for peer in ldp.peers %}
targeted-peer ipv4 {{ peer.address }}
exit
{% endfor %}
advertise-labels for only_lo to any
exit
{% for interface in ldp_interfaces %}
interface {{interface.ldp_interface}}
enable-ldp {{interface.ldp_protocol}}
label-switching
{% endfor %}
sw2.yml
Next, provide the LDP configuration details in the appropriate host_vars file:
osboxes@osboxes:~/playbooks$ cat host_vars/sw2.yml
ldp:
peers:
- address: 1.1.1.1
- address: 3.3.3.3
ldp_interfaces:
- { ldp_interface: eth1, ldp_protocol: ipv4 }
- { ldp_interface: eth2, ldp_protocol: ipv4 }
Here is the overall directory structure of the Ansible playbook and associated files:
osboxes@osboxes:~/playbooks$ tree
.
ansible.cfg
backup
group_vars
ocnos.yml
hosts-net
host_vars
sw2.yml
ldp-playbook.yml
showldp-playbook.yml
templates
ocnos_ldp.j2
ansible.cfg
The following is the content of ansible.cfg file that points to the hosts-net inventory file.
osboxes@osboxes:~/playbooks$ cat ansible.cfg
[defaults]
inventory = hosts-net
host_key_checking = False
retry_files_enabled = False
interpreter_python = auto
osboxes@osboxes:~/playbooks
host-net
The following is the content of the hosts-net inventory file.
osboxes@osboxes:~/playbooks$ cat hosts-net
[ocnos]
sw2 ansible_host=10.12.9.105
osboxes@osboxes:~/playbooks$
ocnos.yml
The following is the content of ocnos.yml in the group_vars folder.
osboxes@osboxes:~/playbooks$ cat group_vars/ocnos.yml
ansible_connection: network_cli
ansible_network_os: ocnos
ansible_become: yes
ansible_become_method: enable
ansible_ssh_user: ocnos
ansible_ssh_pass: ocnos
osboxes@osboxes:
ldp-playbook.yml
The following is the playbook to push the configuration with cli_config module using the template created earlier:
(ansible) osboxes@osboxes:~/playbooks$ cat ldp-playbook.yml
---
- hosts: ocnos
gather_facts: no
tasks:
- name: configure LDP config on OcNOS
cli_config:
config: "{{ lookup('template', 'templates/{{ ansible_network_os }}_ldp.j2') }}"
Running the Playbook
The following is the configuration on the OcNOS device before executing the Ansible Playbook:
OcNOS#show running-config ldp
!
!
OcNOS#
Execute the Ansible Playbook. Below are the logs that display:
(ansible) osboxes@osboxes:~/playbooks$ ansible-playbook ldp-playbook.yml
PLAY [ocnos] ******************************************************************************************************
TASK [configure LDP config on OcNOS] ******************************************************************************
changed: [sw2]
PLAY RECAP ********************************************************************************************************
sw2 : ok=1 changed=1 unreachable=0 failed=0 skipped=0 rescued=0 ignored=0
Next, check the configurations on the OcNOS device, which should show the LDP configurations.
OcNOS#show running-config ldp
!
router ldp
targeted-peer ipv4 1.1.1.1
exit-targeted-peer-mode
targeted-peer ipv4 3.3.3.3
exit-targeted-peer-mode
advertise-labels for only_lo to any
!
!
interface eth2
enable-ldp ipv4
!
interface eth1
enable-ldp ipv4
!
OcNOS#
showldp-playbook.yml
The playbook below shows how to check the runtime status of the LDP protocol through the show ldp session command. It is assumed that the neighboring nodes are configured accordingly to get the LDP session up and running:
osboxes@osboxes:~/playbooks$ cat showldp-playbook.yml
---
- hosts: ocnos
gather_facts: no
tasks:
- name: show LDP config ocnos
cli_command:
command: show ldp session
register: result
- name: debug
debug:
msg: "{{ result.stdout_lines }}"
osboxes@osboxes:~/playbooks$
When you run this playbook, the example below is its output. Parsing of the show command output needs to be done to determine if the runtime status of the protocol is correct:
(ansible) osboxes@osboxes:~/playbooks$ ansible-playbook showldp-playbook.yml
PLAY [ocnos] ******************************************************************************************************
TASK [show LDP config ocnos] **************************************************************************************
ok: [sw2]
TASK [debug] ******************************************************************************************************
ok: [sw2] => {
"msg": [
"Peer IP Address IF Name My Role State KeepAlive UpTime",
"3.3.3.3 eth2 Passive OPERATIONAL 30 03:58:20",
"1.1.1.1 eth1 Active OPERATIONAL 30 03:58:20"
]
}
PLAY RECAP ********************************************************************************************************
sw2 : ok=2 changed=0 unreachable=0 failed=0 skipped=0 rescued=0 ignored=0
(ansible) osboxes@osboxes:~/playbooks$