Nowadays, sysadmins and devops are required to manage large numbers of servers and networks. They have to perform various actions repeatedly, such as installing/provisioning a new server, deploying a package to a group of servers, and rebooting a set of servers at specific times. A configuration management tool like Ansible vs Salt can automate some of these repetitive tasks.
Both Ansible and Salt are configuration management tools, but they are quite different from each other. Below, you can find out more about:
– How Ansible and Salt works,
– The features, advantages, and disadvantages of Ansible,
– The features, advantages, and disadvantages of Salt, and
– Which tools that is more recommended for you.
Ansible is spiritually similar to Salt that it is designed to be streamlined and fast. One big distinction in Ansible’s architecture is that it does not require any agent installation or dependency on the client machine, except for a Python interpreter. See also: Ansible vs Terraform.
Ansible performs all actions through either a standard SSH connection or the Paramiko module which creates a Python interface for SSH2. Don’t worry if the operating system blocks SSH by default, as Ansible can ‘sudo’ to emulate root access.
Configurations and commands in Ansible are executed using the YAML syntax in files called playbooks. You can store and organize your playbooks into templates or packages for future reuse; there are already many shared templates available on Ansible’s Galaxy. You can write Ansible modules in any language that can output JSON modules – the Python base is chosen by default because it is usually pre-installed in many Linux distros.
Advantages of Ansible
The very first advantage of Ansible is the easy deployment and operation. The agent-less design means that you don’t need to install anything on the client side. It is also relatively lightweight to run. Second, the command line interface supports almost any programming language, so it is very flexible and versatile. Third, it has the additional Ansible Tower dashboard for visual management, which may be more convenient especially for beginners.
Disadvantages of Ansible
There are just a few disadvantages of Ansible. First, it is somehow prone to performance issues. This is not always the case, but the performance may fluctuate a little from time to time. Second, the installation is not as customizable as some other tools. It also lacks introspection features, such as the ability to see variable values in a playbook.
Salt is also developed in Python. It was created in response to the limitations of traditional configuration management tools which are Ruby-based and often suffer slow performance. Nevertheless, Salt still uses a server-client architecture which uses a master server that is responsible for managing one or more agents called ‘minions’. Salt supports only Python, and all commands should be written in either Python or PyDSL (a custom DSL). You can download Salt here.
Salt also uses YAML configuration files which you can organize into templates or packages. Communication between the minions and the master server is performed by using the ZeroMq messaging lib over the transport layer. However, ZeroMq is not as secure as SSH due to lacking native encryption. To solve the issue, Salt implements Kevlar, which is an additional security layer with AES encryption. Salt also uses persistent daemons to allow master-minion communication across nodes.
Advantages of Salt
Salt is highly scalable and resilient. It is especially efficient for large-sized networks. This is because of Salt’s multi-master capability. Under a master server, you can deploy another master to control a group of nodes. Such capability allows Salt to be adaptable for a complex environment.
The minions of Salt offer more options and flexibility. You can customize the minions according to your specific needs. Also, the performance is relatively fast, stable, and consistent.
Disadvantages of Salt
Salt only supports Python and PyDSL. So, if you are unfamiliar with either of the two, you will have to learn at least one of them – probably Python, which is a popular programming language that is also used in many other tools.
Salt’s minions are not as efficient as Ansible’s agent-less architecture for small-sized networks. Also, Salt’s GUI is not very good. An experienced user will prefer to use the CLI, which is more mature and efficient.
Ansible vs Salt
|- Agent-less deployment||- Server-client deployment|
|- Supports many programming languages||- Supports Python and PyDSL|
|- The Ansible Tower GUI is good||- The GUI is not really good|
|- Not very scalable||- Quickly scalable and very resilient|
|- May have performance issues on a large, complex deployment||- Stable and consistent performance on a large, complex deployment|
Both Ansible vs Salt are good tools. For a small-sized deployment, Ansible is great. It is more efficient with the agent-less architecture. However, for a large-sized deployment, Salt is the better way to go due to the scalability and stable performance.