Ansible shell Module vs command: Differences, Security & When to Use Each — Video Tutorial

Ready to advance your Ansible expertise? [Explore Linux Administrator](https://jooble.org/jobs-remote-linux-administrator) Job openings today! What is the difference between `command` vs `shell` Ansible modules? These two Ansible modules are confused one for another but they're fundamentally different. Both modules allow you to execute command on a target host but in a slightly different way. I'm Luca Berton and welcome to today's episode of Ansible Pilot. command vs shell command - execute commands against the target Unix-based hosts - it bypasses the shell - always set changed to True shell - execute shell commands against the target Unix-based hosts - redirections and shell's inbuilt functionality - always set changed to True The `command` and `shell` Ansible modules execute commands on the target node. Generally speaking, is always better to use a specialized Ansible module to execute a task. However, sometimes the only way is to execute a Linux `command` via command or `shell` module. Let me reinforce again, you should avoid as much as possible the usage of command/shell instead of a better module. Both modules execute commands on target nodes but in a sensible different way. The `command` modules execute commands on the target machine without using the target shell, it simply executes the command. The target shell is for example the popular `bash`, `zsh`, or `sh`. As a side effect user environment, variable expansions, output redirections, stringing two commands together, and other shell features are not available. On the other side, every command executed using `shell` module has all shell features so it could be expanded in runtime. From the security point of view`command` module is more robust and has a more predictable outcome because it bypasses the `shell`. Both modules returned **always** changed status because Ansible is not able to predict if the execution has or has not altered the target system. command module - Execute commands on targets The "command" module is the default module in Ansible Ad-hoc mode. The command module is able to execute only the binaries on remote hosts. The `command` module won't be impacted by local shell variables because it bypasses the shell. At the same time, it may not be able to run "shell" built-in features and redirections. shell module - Execute shell commands on targets The `shell` Ansible module is potentially more dangerous than the command module and should only be used when you actually really need the shell functionality. So if you're not stringing two commands together (using pipes or even just `&&` or `;`), you don't really need the shell module. Similarly, expanding shell variables or file global requires the shell module. If you're not using these features, don't use the shell module. Sometimes it's the only way, I know. Links - [ansible.builtin.shell](https://docs.ansible.com/ansible/latest/collections/ansible/builtin/shell_module.html) - [ansible.builtin.command](htt