vrf_command

This Ansible Network role provides the ability to send VRF-aware network commands to network devices dynamically. Currently, this is supported on IOS / EOS / NXOS devices.

The role is intended to be an enhancement of the default behavior of the following modules:

• ios_command
• nxos_command
• eos_command

Demonstration

See Example Playbook 2 for the playbook details for this example demonstration.

Requirements

None.

Role Variable

The following value should be updated based on your requirements (see defaults/main.yml):

vrf_command_list:
  - "show ip route vrf <vrf>"
  - "show version"

The vrf_command_list should be updated to include all commands that the you wish to run against your network devices. To make a show command behave in a VRF-aware manner, the syntax <vrf> should be used as can be seen above.

The <vrf> in the command will be replaced with the VRFs available on the device including the global table. For example, if a device has the VRFs dev and prod, the show ip route vrf <vrf> command will dynamically expand out to the following:

• show ip route
• show ip route vrf dev
• show ip route vrf prod

Note that you can run regular non-VRF related commands as well via this role.

Output Variable

The role generates a custom output variable for user convenience called vrf_command_output.

The format of the data structure is as follows:

vrf_command_output:
  - command: "show ip route vrf dev"
      failed: False
      output: "...77.77.77.0 is directly connected, FastEthernet1/0\n..." (omitted)
  - command: "show blah blah"
      failed: True
      output: "...% Invalid input detected at..." (omitted)

The data structure returns a list of values. Within each list item are three keys.

• command - The show command that was run against the network device.
• failed - Boolean where true is command failed and false is command executed successfully.
• output - The output of the show command.

Example Playbook 1

The below example playbook demonstrates basic usage on how the role can be used.

- hosts: all

  vars:
    vrf_command_list:
      - "show ip interface brief vrf <vrf>"
      - "show ip route vrf <vrf>"
      - "show interface status"
      - "show version"
      
  roles:
      - syedur_rahman.vrf_command

Example Playbook 2

The below example playbook demonstrates manipulating the vrf_command_output to dump to text files.

- hosts: all

  vars:
    vrf_command_list:
      - "show ip route vrf <vrf>"
      
  roles:
    - syedur_rahman.vrf_command

- hosts: localhost

  tasks:
  - template:
      src: "show_command.j2"
      dest: "{{ item }}.txt"
    loop: "{{ groups['all'] }}"

With the below being the show_command.j2 template.

{% for show_command_info in hostvars[item]['vrf_command_output'] %}
~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~
{{ show_command_info['command'] }}
~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~
{{ show_command_info['output'] }}
{% endfor %}

This results in the following type of output file per device.

~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~
show ip route vrf management
~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~
IP Route Table for VRF "management"
'*' denotes best ucast next-hop
'**' denotes best mcast next-hop
'[x/y]' denotes [preference/metric]
'%<string>' in via output denotes VRF <string>

192.168.12.0/24, ubest/mbest: 1/0, attached
    *via 192.168.12.135, mgmt0, [0/0], 05:12:12, direct
192.168.12.135/32, ubest/mbest: 1/0, attached
    *via 192.168.12.135, mgmt0, [0/0], 05:12:12, local

~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~
show ip route
~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~
IP Route Table for VRF "default"
'*' denotes best ucast next-hop
'**' denotes best mcast next-hop
'[x/y]' denotes [preference/metric]
'%<string>' in via output denotes VRF <string>

2.2.2.0/24, ubest/mbest: 1/0, attached
    *via 2.2.2.2, Lo100, [0/0], 05:12:28, direct
2.2.2.2/32, ubest/mbest: 1/0, attached
    *via 2.2.2.2, Lo100, [0/0], 05:12:28, local
2.3.4.0/24, ubest/mbest: 1/0, attached
    *via 2.3.4.5, Lo23, [0/0], 05:12:28, direct
2.3.4.5/32, ubest/mbest: 1/0, attached
    *via 2.3.4.5, Lo23, [0/0], 05:12:28, local

License

MIT

Author Information

This role was created in 2020 by Syedur Rahman.