Everything you have scripted so far in this series has been imperative: do this, then this, on these devices. Configuration management tools flip the model. You declare the state you want, and the tool figures out whether anything needs doing. That idea (exam topic 6.6 names Ansible, Puppet, and Chef) is best understood by running it, so in this lab you install Ansible on the HOST1 automation node, aim it at all four lab devices, and back up every config with an eleven-line playbook. Part of the PingLabz CCNA Automation Labs, all output captured live from Cisco IOS XE 17.18.
You will also hit a real failure on the way (paramiko refusing three unknown host keys) and fix it the way working engineers do. The failure stays in the article because meeting it here, in a lab, is worth more than meeting it for the first time in production.
What you will learn
- What "agentless" actually means and why it matters for network gear that cannot run agents.
- Ansible's three moving parts: inventory, modules, playbooks.
- How to run ad-hoc commands and a YAML playbook against Cisco IOS using the cisco.ios collection.
- Idempotence in action: what
changedvsokmeans in a PLAY RECAP.
