Ansible
A versatile orchestration engine that can automate systems and apps. Instead of a custom scripting language or code, it is very simple and shell based. It is also agent-less, so you can just start using it right away and get things done
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Bento
A modularized collection of Packer definitions for building machine images. A good place to start with Packer.
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Puppet
Puppet is a tool designed to manage the configuration of Unix-like and Microsoft Windows systems declaratively.
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SaltStack
Salt is a powerful and different approach to infrastructure management, by focusing on high speed communications between large number of systems, and can perform orchestration, remote code execution and much more.
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Vagrant
Vagrant is a cross platform tool to create, boot, configure and destroy development environments. It provides a simple configuration-based approach to take a base image, boot it up, provision it (using any other provisioners), SSH, port forward, and much more. It automates the process of booting up and configuring virtual machines. It supports various providers like VirtualBox, VMWare, AWS, LXC, etc.
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