> ## Documentation Index > Fetch the complete documentation index at: https://notes.kodekloud.com/llms.txt > Use this file to discover all available pages before exploring further. # Ansible Loops > Learn to simplify Ansible playbooks using loops for efficient task execution and reduced code duplication. In this tutorial, you'll learn how to simplify your Ansible playbooks by using loops. Loops help you execute the same task multiple times by iterating over a list of items, making your playbooks more structured, maintainable, and efficient. A common scenario is creating multiple users on target systems without the need to duplicate tasks. ## Basic Looping Example Consider a traditional playbook that creates individual users by repeating nearly identical tasks: ```yaml theme={null} - name: Create users hosts: localhost tasks: - user: name: joe state: present - user: name: george state: present - user: name: ravi state: present - user: name: mani state: present - user: name: kiran state: present - user: name: jazlan state: present - user: name: emaan state: present - user: name: mazin state: present - user: name: izaan state: present - user: name: mike state: present - user: name: menaal state: present - user: name: shoeb state: present - user: name: rani state: present ``` This approach results in a lot of duplicated code. Instead, using a loop allows the `user` module to be called repeatedly for each value in the list. Here's how you can streamline the playbook: ```yaml theme={null} - name: Create users using a loop hosts: localhost tasks: - user: name: "{{ item }}" state: present loop: - joe - george - ravi - mani - kiran - jazlan - emaan - mazin - izaan - mike - menaal - shoeb - rani ``` In this improved version, the `loop` directive iterates over the usernames. For each iteration, the current value is assigned to the variable `item`, which you reference using `{{ item }}`. This reduces repetition significantly and enhances readability. ## Visualizing Loop Execution To help you grasp how loops execute tasks, imagine the loop expanded manually: ```yaml theme={null} - name: Create users (expanded loop) hosts: localhost tasks: - user: name: "joe" state: present - user: name: "george" state: present - user: name: "ravi" state: present - user: name: "mani" state: present # ... and so on for each user ``` Each repetition of the task uses a different value from the list in exactly the same manner as the loop. ## Looping Over an Array of Dictionaries When your requirements include passing multiple parameters (like a username along with a user ID), you can iterate over a list of dictionaries. In each iteration, the dictionary’s keys (e.g., `name` and `uid`) can be accessed for dynamic task creation: ```yaml theme={null} - name: Create users with UID assignments hosts: localhost tasks: - user: name: "{{ item.name }}" state: present uid: "{{ item.uid }}" loop: - name: joe uid: 1010 - name: george uid: 1011 - name: ravi uid: 1012 - name: mani uid: 1013 - name: kiran uid: 1014 - name: jazlan uid: 1015 - name: emaan uid: 1016 - name: mazin uid: 1017 - name: izaaan uid: 1018 - name: mike uid: 1019 ``` By using dictionaries, each loop iteration can handle intricate data, making your playbook versatile and powerful. ## The with\_items Directive Prior to the introduction of the `loop` directive, Ansible used `with_items` for iterating over lists. Although both methods produce the same result for simple use cases, it is recommended to use the newer `loop` directive to enhance readability and consistency in your playbooks. ```yaml theme={null} - name: Create users with with_items hosts: localhost tasks: - user: name: "{{ item }}" state: present with_items: - joe - george - ravi - mani ``` For better clarity and future-proof playbooks, prefer using `loop` over `with_items`. ## Other Looping Directives and Lookup Plugins Beyond basic loops, Ansible offers several looping directives powered by lookup plugins. These plugins allow iteration over various data sources such as files, URLs, and even databases. Below are some examples: ```yaml theme={null} - name: Create users using with_items hosts: localhost tasks: - user: name: "{{ item }}" state: present with_items: - joe - george - ravi - mani - name: View configuration files hosts: localhost tasks: - debug: var: item with_file: - "/etc/hosts" - "/etc/resolv.conf" - "/etc/ntp.conf" - name: Retrieve data from multiple URLs hosts: localhost tasks: - debug: var: item with_url: - "https://site1.com/get-servers" - "https://site2.com/get-servers" - "https://site3.com/get-servers" - name: Check multiple MongoDB instances hosts: localhost tasks: - debug: msg: "DB={{ item.database }} PID={{ item.pid }}" with_mongodb: - database: dev connection_string: "mongodb://dev.mongo/" - database: prod connection_string: "mongodb://prod.mongo/" ``` Here is a quick overview of some common lookup plugins: | Lookup Plugin | Use Case | | -------------------------- | ------------------------------------------ | | with\_dict | Looping over dictionary key/value pairs | | with\_etcd | Retrieving data from an etcd datastore | | with\_env | Iterating through environment variables | | with\_filetree | Looping through a directory tree | | with\_ini | Parsing INI files | | with\_inventory\_hostnames | Accessing hostnames from an inventory file | | with\_k8s | Interacting with Kubernetes objects | | with\_openshift | Interacting with OpenShift | | with\_password | Generating or handling passwords | | with\_sequence | Creating a sequence of numbers | | with\_subelements | Iterating over nested lists | These lookup plugins can be considered as custom scripts that enable you to access data from diverse sources, further extending Ansible’s functionality. ## Conclusion Understanding and utilizing loops in Ansible is critical for creating efficient, scalable, and maintainable playbooks. By leveraging loops, whether simple arrays or complex dictionaries, you can significantly reduce code duplication and enhance the clarity of your automation scripts. Experiment with different looping constructs to find the best fit for your automation needs. For additional guidance, explore the [Ansible Documentation](https://docs.ansible.com/ansible/latest/index.html).