Set sysctl kernel parameters - Ansible module sysctl

How to automate the setting or verification of the Linux sysctl kernel parameter “vm.swappiness” to 5 with Ansible.

How to set the sysctl kernel parameters with Ansible?

I'm going to show you a live Playbook and some simple Ansible code.

I'm Luca Berton and welcome to today's episode of Ansible Pilot.

Ansible set sysctl kernel parameters

ansible.posix.sysctl

Manage entries in sysctl.conf

Today we're talking about the Ansible module sysctl.

The full name is ansible.posix.sysctl, which means that is part of the collection of modules "ansible.posix" to interact with POSIX platforms.

The purpose of the module is to manage entries in the sysctl.conf file.

Parameters

name string (key) - Parameter name

value string - Parameter value

reload boolean - yes/no

state string - present/absent

sysctl_file string - "/etc/sysctl.conf"

sysctl_set string - no/yes - sysctl -w

ignoreerrors boolean - no/yes

Let me summarize the parameters of sysctl module.

The only required is "name", where you specify the parameter name to access or edit.

The parameter "value" sets the value of the sysctl parameter.

The parameter "reload", default to yes, reload the configuration file if any changes occur.

The parameter "state" sets the presence or absence of the parameter in the sysctl file.

The parameter "sysctl_file" allows specifying the configuration file for sysctl, default to "/etc/sysctl.conf".

The parameter "sysctl_set" allows you to configure a parameter permanently, that survives after reboot.

The parameter "ignoreerrors" allow you to ignore errors about unknown keys, default to "no".

Links

https://docs.ansible.com/ansible/latest/collections/ansible/posix/sysctl_module.html

## Playbook

Ansible set sysctl kernel parameters.

code

``yaml


---
name: sysctl module Playbook
  hosts: all
  become: true
  vars:
    sysctl_name: "vm.swappiness"
    sysctl_value: "5"
  tasks:
    - name: set sysctl
      ansible.posix.sysctl:
        name: "{{ sysctl_name }}"
        value: "{{ sysctl_value }}"
        state: present
        sysctl_set: true
        reload: true



execution

`bash


$ ansible-playbook -i virtualmachines/demo/inventory sysctl/sysctl.yml
PLAY [sysctl module Playbook] *
TASK [Gathering Facts] 
ok: [demo.example.com]
TASK [ansible.posix.sysctl] *
changed: [demo.example.com]
PLAY RECAP **
demo.example.com           : ok=2    changed=1    unreachable=0    failed=0    skipped=0    rescued=0    ignored=0



idempotency

``bash

$ ansible-playbook -i virtualmachines/demo/inventory sysctl/sysctl.yml

PLAY [sysctl module Playbook] *

TASK [Gathering Facts]

ok: [demo.example.com]