Today will be a touch shorter post, but it is good to be back at it. In this post I will be taking a quick look around at the asa_command module, as we start down the path with looking at the ASA modules in Ansible. This is spurned on a little bit by Ansible 2.8 coming out with an Object Group specific module. I will be looking into that further in a future post.

For the set of posts regarding the ASA, we will be starting with a pretty bare configuration on the device. We will have just a management IP address and the ability to SSH to the device.

Module Documentation

Module documentation page can be found here.

Lab Configuration

The device has bare basic configuration on it. Here we see that it has just a management IP address on it.

fw01# show int ip brie
Interface                  IP-Address      OK? Method Status                Protocol
GigabitEthernet0/0         unassigned      YES unset  administratively down up  
GigabitEthernet0/1         unassigned      YES unset  administratively down up  
GigabitEthernet0/2         unassigned      YES unset  administratively down up  
Management0/0              172.16.0.254    YES CONFIG up                    up

Using the playbook

Parameters

There are a couple of key parameters on this module for getting started are:

• commands: A list of commands to send to the device; this can be one, or several commands within a list
• context: used for firewalls in multi-context mode, which context do you want to run the command(s) in

Simple first Playbook

This is a simple playbook that will issue two commands. We will access both of them in different tasks within the play. Taking a look at the play we are executing the task with two commands, a show int ip brie and a ping to Google DNS.

Playbook

---
# yamllint disable rule:truthy
# yamllint disable rule:line-length
- name: ASA Command Output
  connection: network_cli
  hosts: asa_firewalls
  gather_facts: no
  become: yes
  become_method: enable

  tasks:

    - name: "TASK 1: Read output from ASA"
      asa_command:
        commands:
          - show int ip brief
          - ping 8.8.8.8
      register: output

    - name: "TASK 2: Print output of show interfaces"
      debug:
        msg: "{{ output.stdout_lines.0 }}"

    - name: "TASK 3: Print output of pinging Google DNS"
      debug:
        msg: "{{ output.stdout_lines.1 }}"

Tasks High Level

TASK 1 is when Ansible logs into the device and issues the two commands.
TASK 2 we get the expected output of the show int ip brie and the commands TASK 3 we see that the device is able to successfully ping Google DNS

These are the tasks that are to be run via the playbook broken out:

cat asa_command_demo.yml | grep TASK
    - name: "TASK 1: Read output from ASA"
    - name: "TASK 2: Print output of show interfaces"
    - name: "TASK 3: Print output of pinging Google DNS"

Playbook Run

Execution of the playbook:

PLAY [ASA Command Output] *********************************************************************

TASK [TASK 1: Read output from ASA] ***********************************************************
ok: [asa1]

TASK [TASK 2: Print output of show interfaces] ************************************************
ok: [asa1] => {
    "msg": [
        "Interface                  IP-Address      OK? Method Status                Protocol",
        "GigabitEthernet0/0         unassigned      YES unset  administratively down up  ",
        "GigabitEthernet0/1         unassigned      YES unset  administratively down up  ",
        "GigabitEthernet0/2         unassigned      YES unset  administratively down up  ",
        "Management0/0              172.16.0.254    YES CONFIG up                    up"
    ]
}

TASK [TASK 3: Print output of pinging Google DNS] *********************************************
ok: [asa1] => {
    "msg": [
        "Type escape sequence to abort.",
        "Sending 5, 100-byte ICMP Echos to 8.8.8.8, timeout is 2 seconds:",
        "!!!!!",
        "Success rate is 100 percent (5/5), round-trip min/avg/max = 20/104/190 ms"
    ]
}

PLAY RECAP ************************************************************************************
asa1                       : ok=3    changed=0    unreachable=0    failed=0    skipped=0    rescued=0    ignored=0

Access Multiple Commands

This is another example of how to issue multiple commands against a device within a single task. For a deeper dive on that you can see an earlier post here.

Summary

This is a solid starting out module for working with ASA firewalls. It does come in very handy with dealing and gathering information from the ASA firewall platform. I have used this for several things within a production environment, primarily for data gathering. Hopefully coming up I will be able to expand on this further in building out an ASA firewall.

Hope this was helpful!