Ansible vs. Salt: What you need to know

Ansible and Salt are community open source IT automation tools. Both can simplify IT operations and DevOps work by automating routine tasks such as configuring and provisioning systems, deploying software, and managing updates across large numbers of servers or endpoint devices.

Ansible is known for its ease of use, thanks to a more flexible agentless approach, which requires no additional software to be installed on the targets being automated. By contrast, Salt takes an agent-based approach, meaning additional software is required on each machine. For approaches to automation itself, both Ansible and Salt are Python-based, with Ansible relying on YAML configuration files and procedural automation that define steps to be run in order, and Salt using a small subset of YAML to map over commonly used data structures, like lists and dictionaries. 

This article will help explain the similarities and differences between Ansible and Salt in greater detail.

Where do Ansible and Salt fit in the wider landscape of IT automation tools? Ansible, Salt, Puppet, and Chef are 4 commonly used open source IT automation tools. Each takes a distinct approach to automation, and all are available as enterprise solutions sold by different software companies. Many IT organizations use more than 1 solution for different purposes—or even in combination.

• Ansible was acquired by Red Hat in 2015 and is available as Red Hat® Ansible® Automation Platform.
• Salt (commercially known as SaltStack) was acquired by VMWare in 2020, to be included as part of the vRealize Automation portfolio that was recently rebranded as VMware Aria Automation. VMware was acquired by Broadcom in 2022. 
• Puppet is supported by Perforce and is available in a series of commercial products including Puppet Enterprise and Puppet Bolt.
• Chef was acquired by Progress in 2020 and is available in a series of commercial products including Chef Enterprise Automation Stack. 

Ansible

Ansible is an open source, command-line IT automation software application written in Python. It can configure systems, deploy software, and orchestrate advanced workflows to support application deployment, system updates, networking configuration and operation, and more. Red Hat Ansible Automation Platform is a subscription product built on the foundations of Ansible with numerous enterprise features.

Ansible’s strengths come from its community. Its main GitHub repository draws thousands of contributors, and has tens of thousands of repositories that depend on it, as of fall 2022. A popular user conference, AnsibleFest, takes place every year, and Ansible Meetups happen on a frequent basis around the world. This enthusiastic user community reflects a large pool of Ansible expertise, with contributors who keep Ansible robustly integrated with other popular software projects. Ansible users can access hundreds of modules and plugins that help extend its capabilities.

Ansible is designed with a focus on simplicity and ease-of-use. It also emphasizes security and reliability, featuring minimal moving parts. It uses OpenSSH for transport (with other transports and pull modes as alternatives), and uses a human-readable language that helps users get started quickly without a lot of training.

Ansible uses the concepts of a control node (where Ansible is executed from) and managed nodes (the devices being automated—often a Linux® or Windows machine). Since Ansible is agentless, it can communicate with devices without requiring an application or service to be installed on the managed node. Ansible Automation Platform can spread automation jobs out across execution nodes using a technology called automation mesh.  

Ansible users can finely orchestrate different parts of their infrastructure using Ansible Playbooks, which are files written in human-readable YAML. Ansible uses a procedural (or imperative) programming approach, which tries to preserve the configuration of an IT infrastructure by defining the steps to reach a desired state.

Salt

Salt is an open source IT automation application that is modular and also written in Python. Designed for high-speed data collection and execution, Salt is a configuration management tool with a lightweight ZeroMQ messaging library and concurrency framework that establishes persistent Transmission Control Protocol (TCP) connections between the server and agents. 

Like Ansible, Salt uses YAML, which makes it easy to learn and manage. Its agent-based architecture, however, can pose a significant learning curve to new users and prove challenging for seasoned DevOps professionals. In this context, the server is called a salt master and clients are called salt minions, which run as agents in the client machine. Multiple masters can be configured, and if one master is down, agents connect with another master in the list. Since servers push configurations to all the clients, immediate remote execution occurs. 

Since SaltStack’s acquisition by VMware, the Salt open source community has decreased in size—with fewer projects dependent on it than Ansible, based on GitHub insights in fall of 2022. And following VMware’s acquisition by Broadcom in 2022, the focus is more on automating VMware products and less on networking and multivendor or multipurpose use cases, resulting in an accelerated IT skill gap and uncertain corporate support for the Salt community.     

Agent-based architecture describes an infrastructure and automation model that requires specific software called agents to run on managed environments. The agent and all of its dependencies need to be installed on every target node, requiring additional security checks and rules. This can become a challenge when it’s time to automate objects on which the agent is unavailable or not allowed to run. It also requires agents to be maintained.

Agentless architecture, which Ansible uses, describes a way to automate and manage IT devices without requiring any agent software installed on managed environments. The control software connects to remote machines over Secure Shell (SSH) and begins managing them without a lengthy setup process. This architecture eliminates the need to maintain a deployment system once the configuration is done.

Configuration managament is a process for maintaining computer systems, servers, and software in a consistent desired state. It ensures that a system performs as expected as changes are made over time. Configuration management can be automated—reducing cost, complexity, and the risk of manual errors.  

DevOps and DevSecOps stand for development operations and development, security, and operations. They are approaches to culture, automation, and platform design that integrates security as a shared responsibility throughout the entire IT life cycle. DevOps and DevSecOps are the same thing, in that it was always intended that security be part of the DevOps approach. Many have switched to referring to it as DevSecOps, however, to make this inclusion explicit.

YAML stands for Yet Another Markup Language (or YAML Ain’t Markup Language), and is a data serialization language that is often used for writing configuration files. YAML is designed to be human-readable and easy to understand, and can be used in conjunction with other programming languages. YAML is a superset of JavaScript Object Notation (JSON).

Choosing an automation solution requires evaluating not just the features available today but also considering the longer-term outlook for the platform. Ansible stands out for its active open source community and backing from Red Hat.

It’s also common for organizations to use multiple automation solutions. Ansible connects to a large ecosystem of supported integrations, and can be used in conjunction with many other automation and configuration management tools—as an orchestrator of automators. In addition, Ansible can automate systems on public cloud hyperscalers such as Amazon Web Services (AWS), Microsoft Azure, and Google Cloud Platform (and many more).

Compared to Salt, Ansible is a preferred choice for users who favor simplicity, ease of use, and an agentless automation solution. It also benefits from a large community of contributors and partnerships, is widely adopted in different IT domains such as network and infrastructure automation, and is highly regarded for its integration with other tools.

With open source at its core, Red Hat Ansible Automation Platform is a security-hardened, tested subscription product that offers full life cycle support for organizations. Its upstream project, Ansible, benefits from the experience and intelligence of its thousands of global contributors. 

Ansible Automation Platform includes numerous upstream components, more than 140 Red Hat Ansible Certified Content Collections from 60+ partners, and as-a-service return on investment (ROI) tools that take the guesswork out of installing, configuring, and supporting automation in your organization. It creates an end-to-end automation experience aimed at cross-functional teams while providing a plug-and-play experience between automation developers, engineers, and operations teams.

Red Hat Ansible Automation Platform’s features—like automation analytics and Red Hat Insights—provide accessible information on the performance of your automation, allowing you to measure your impacts and monitor or resolve issues with greater precision. Automation mesh lets you scale control and execution capacity independently, delivering automation closer to the endpoints that need it, with little or no downtime, allowing you to reach a consistent automation experience from the datacenter, to the cloud, to the edge locations

As a choice for agentless, easy-to-use IT automation, Ansible stands out for its simplicity, flexibility, and strong user community.