Packer vs Salt: What are the differences?

Introduction

Packer and Salt are both powerful tools used in the realm of software development and infrastructure management. However, they serve different purposes and have distinct features that set them apart.

1. Image-based Provisioning with Packer: Packer focuses on image-based provisioning, which involves creating pre-configured machine images that can be easily replicated across multiple platforms and environments. It allows developers to define machine configurations in a JSON or HCL (HashiCorp Configuration Language) template, enabling them to provision identical machine images for different virtualization platforms, cloud providers, or container runtimes. Packer automates the creation of these images, ensuring consistency and reducing the time and effort required for deployment.

2. Configuration Management with Salt: On the other hand, Salt is primarily a configuration management system. It enables the management and automation of software configuration across a network of devices or systems. Salt employs a master-slave architecture, where the Salt master acts as a central control server, managing and distributing configurations to Salt minions (client nodes). With Salt, administrators can define and enforce desired states for systems, install software packages, apply configurations, and execute remote commands across multiple machines.

3. Build vs. Deployment: Packer is primarily used during the build phase of infrastructure management. It helps streamline the process of creating and distributing machine images for different platforms. In contrast, Salt focuses on the deployment and management phase, offering extensive capabilities for configuration management and remote execution of commands on target systems.

4. Platform Independence: Packer provides a platform-agnostic approach to infrastructure provisioning and eliminates the need for custom configuration scripts or setup procedures. It supports the creation of machine images for various platforms, including virtual machines (e.g., VMware, Hyper-V), cloud providers (e.g., AWS, Azure), and container runtimes (e.g., Docker). Salt, on the other hand, works across a wide range of operating systems and platforms, making it a versatile tool for managing diverse infrastructure environments.

5. Scalability and Distributed Execution: Salt's architecture is designed to handle large-scale deployments and offers robust support for distributed execution. With Salt, administrators can easily manage configurations across hundreds or thousands of machines simultaneously. Packer, in contrast, focuses on the creation of machine images and does not offer the same level of scalability or distributed execution capabilities as Salt.

6. Focus and Extensibility: Packer is primarily focused on the creation and distribution of machine images, ensuring the consistency and repeatability of infrastructure setups. It provides a framework for extensibility, allowing developers to define their own builder plugins to accommodate custom image creation scenarios. Salt, on the other hand, emphasizes the ongoing management and configuration of systems, offering a wide range of modules and states for various administrative tasks.

In Summary, Packer specializes in image-based provisioning, enabling the creation and replication of machine images across different platforms, while Salt focuses on configuration management, allowing administrators to manage and enforce desired states across a network of devices.