- name: Validate unique list hosts: localhost
vars:
items: [1, 2, 3, 4, 5] tasks:
- name: Ensure uniqueness
fail:
msg: "List contains duplicates"
when: items | length != items | unique | length
Explanation:
By comparing the length of the original and deduplicated list, this check ensures all elements are unique.

ansible-galaxy collection list
Explanation:
The list command displays all installed collections, confirming the availability of required collections.

- name: Add DNS entry hosts: web1
tasks:
- name: Update DNS records
command: echo "web1 IN A 192.168.1.10" >> /etc/dns/zone.file
delegate_to: dns_server
Explanation:
Delegating DNS management tasks to a specific server ensures centralized and consistent DNS configuration.

echo "ansible_http_proxy: http://proxy.example.com:8080" > host_vars/web2.yml
Explanation:
Using proxy variables ensures Ansible tasks can access external resources through the specified proxy server.

- name: Check http_port hosts: web1
tasks:
- fail:
msg: "http_port is undefined"
when: http_port is not defined
Explanation:
Conditional checks prevent runtime errors by verifying required variables before task execution.