Large Scale Deployments

Overview

Strategies and techniques for scaling Ansible to manage thousands of nodes efficiently.

Architecture Patterns

Control Node Architecture

# Example inventory for hierarchical structure
[top_level]
region_1_controller
region_2_controller

[region_1]
app_server_[1:100]

[region_2]
app_server_[101:200]

Pull Mode Architecture

# ansible-pull configuration
- name: Pull-based deployment
  hosts: localhost
  tasks:
    - name: Update local repo
      git:
        repo: https://github.com/org/ansible-config.git
        dest: /etc/ansible/local

Scaling Strategies

Horizontal Scaling

# Parallel execution across regions
- hosts: all
  serial: "30%"
  strategy: free
  tasks:
    - name: Deploy application
      include_role:
        name: app_deploy

Load Distribution

Multiple control nodes
Regional controllers
Task delegation

Resource Management

Memory Optimization

# ansible.cfg optimizations
[defaults]
forks = 50
gathering = smart
fact_caching = redis
fact_caching_timeout = 86400

Network Optimization

# Batch operations
- name: Batch package updates
  package:
    name: "{{ item }}"
    state: latest
  loop: "{{ package_list | batch(100) | list }}"

Infrastructure Design

Network Architecture

Control plane design
Network segmentation
Load balancing

High Availability

# HA configuration example
- name: Configure HA cluster
  hosts: control_nodes
  roles:
    - role: ha_cluster
      vars:
        cluster_name: ansible_ha
        cluster_members: "{{ groups['control_nodes'] }}"

Monitoring & Metrics

Performance Monitoring

- name: Deploy monitoring agents
  hosts: all
  roles:
    - role: monitoring
      vars:
        metrics_server: monitoring.example.com
        collection_interval: 60

Scaling Metrics

Node performance
Network latency
Task execution time

Best Practices

Code Organization

# Role-based structure
roles/
  common/
    tasks/
      main.yml
    handlers/
      main.yml
  web/
    tasks/
      main.yml
  database/
    tasks/
      main.yml

Version Control

Infrastructure as Code
Change management
Release strategy

Troubleshooting at Scale

Debug Strategies

- name: Debug task
  debug:
    var: hostvars[inventory_hostname]
  when: debug_enabled | default(false)

Common Issues

Network bottlenecks
Resource constraints
Task timing issues

Scaling Checklist

[ ] Architecture review
[ ] Resource optimization
[ ] Network design
[ ] Monitoring setup
[ ] HA implementation
[ ] Performance testing