Configuration Management (CM)

• Consider the following application
  
• To host the application on servers, we need to do some configurations (updating os, installing softwares, changing configuration files etc)
• One option of acheiving this is
  • manual (use admin)
• Other options (Reducing time to market)
  • Scripts (Shell scripts or Powershell scripts):
    • Procedural approach (how to do it)
  • Configuration Management uses Declarative approach where we express our desired state (What we want) (Declarative Programming)
• Idempotance: CM executions give same result irrespective of number of executions.
• CM Tools:
  • Ansible
  • Chef
  • Puppet
  • Salt Stack
  • Powershell DSC

Ansible

• Ansible is widely used in
  • DevOps for CM
  • IT for infra mangement and also in Data center automations.
• Push based CM vs Pull Based CM
  
  
• Ansible needs
  • An service account or a user to login into nodes
  • Credentials
  • Python on linux nodes