Which tool functions in a push model, supports languages like Python or Ruby, and does not require an agent to be installed per host?

Ansible is an automation engine that operates on a push model, where a central control node initiates and pushes configurations to managed hosts. It is distinguished by its agentless architecture, communicating with managed nodes typically via standard protocols like SSH for Linux/Unix systems or WinRM for Windows. This eliminates the need to install and maintain a dedicated agent on each host. Ansible playbooks are written in YAML, but its modules—the units of work that are executed on remote hosts—can be written in any language, with Python being the most common. This combination of features directly matches all the requirements stated in the question.

A. Puppet: Puppet primarily uses a pull model and requires a dedicated agent to be installed on each managed host to fetch configurations from the master server.

C. Saltstack: Saltstack's primary architecture requires an agent, called a Salt Minion, to be installed on managed nodes, which maintains a persistent connection to a Salt Master.

D. Chef: Chef operates primarily in a pull model, where a Chef client (agent) installed on each node pulls its configuration from a central Chef server.

1. Ansible Documentation

"How Ansible works": "Ansible is an agentless automation tool... Ansible connects to your nodes and pushes out small programs

called 'Ansible modules' to them. These programs are written to be resource models of the desired state of the system... Ansible modules can be written in any language that can return JSON (Ruby

Python

bash

and so on)."

Source: Red Hat

Inc.

Ansible Documentation

ansible.com/how-ansible-works.

2. Puppet Documentation

"Puppet's architecture": "In agent/master Puppet

an agent node sends facts to a master node and requests a catalog. The master compiles and returns that node's catalog

which the agent applies."

Source: Puppet by Perforce

Puppet Documentation

puppet.com/docs/puppet/latest/architecture.html.

3. Chef Documentation

"Chef Infra Client Overview": "Chef Infra Client is an agent that runs locally on every node that is under management by Chef Infra Server... During a Chef Infra Client run

it performs all of the steps that are required to bring a node into the state that is described by the run-list and cookbook recipes."

Source: Progress Software Corporation

Chef Documentation

docs.chef.io/chefinfraclient/.

4. Salt Project Documentation

"Salt architecture": "The Salt master is the central control bus for the minions... The Salt minion is the agent that receives commands from the Salt master and performs the requested tasks."

Source: Salt Project

Salt Documentation

docs.saltproject.io/en/latest/topics/overview.html#salt-architecture.