Automate Storage Device Management in RHEL with Ansible #
In this tutorial, we will explore how to automate common Red Hat Certified System Administrator (RHCSA) tasks related to storage devices using Ansible. The focus will exclusively be on RHEL (Red Hat Enterprise Linux) systems, ensuring all commands and modules are compatible with this distribution as required by the RHCE (Red Hat Certified Engineer) exam objectives.
Introduction #
Managing storage devices efficiently is critical in any system administration role, especially in enterprise environments. Ansible, an open-source automation tool, simplifies this process by enabling administrators to automate the configuration and management of storage devices across multiple systems.
This tutorial will cover:
- Setting up Ansible for RHEL
- Automating the creation and management of physical volumes, volume groups, and logical volumes
- Formatting and mounting filesystems
- Ensuring idempotency and error handling in Ansible playbooks
Prerequisites #
- A RHEL 8 or later system
- Ansible 2.9 or later installed on a control node (which can be the same as the managed node)
- Sudo privileges on the managed node(s)
Step-by-Step Guide #
Step 1: Setting Up Ansible #
First, ensure that Ansible is installed on your control node:
sudo dnf install ansible
Create an inventory file /etc/ansible/hosts
and add the managed node(s):
[storage-servers]
rhel-server ansible_host=192.168.1.100
Test the connection:
ansible -m ping rhel-server
Step 2: Creating Physical Volumes #
Create a playbook create_pv.yml
to automate the creation of physical volumes:
- hosts: storage-servers
become: true
tasks:
- name: Install required packages
dnf:
name: lvm2
state: present
- name: Creating Physical Volume
community.general.lvg:
pvs: /dev/sdb
state: present
Run the playbook:
ansible-playbook create_pv.yml
Step 3: Creating Volume Groups and Logical Volumes #
Extend the playbook to create a volume group and a logical volume:
- name: Creating Volume Group
community.general.lvg:
vg: vg_data
pvs: /dev/sdb
state: present
- name: Creating Logical Volume
community.general.lvol:
vg: vg_data
lv: lv_data
size: 20G
state: present
Step 4: Formatting and Mounting Filesystems #
Now add tasks to format the logical volume and mount it:
- name: Formatting the Logical Volume
community.general.filesystem:
fstype: xfs
dev: /dev/vg_data/lv_data
- name: Mounting the Logical Volume
ansible.builtin.mount:
path: /data
src: /dev/vg_data/lv_data
fstype: xfs
state: mounted
opts: defaults
Step 5: Ensure Idempotency #
Ensure that the playbook is idempotent by handling conditions where the disk might already be partitioned or the filesystem might already be mounted:
- name: Check if /dev/sdb is already a PV
community.general.lvg:
pvs: /dev/sdb
state: query
register: pv_check
- name: Creating Physical Volume
community.general.lvg:
pvs: /dev/sdb
state: present
when: pv_check.vgs == []
Conclusion #
In this tutorial, we’ve covered how to automate the management of storage devices in RHEL using Ansible. By using Ansible playbooks, we can efficiently handle the creation, configuration, and mounting of physical volumes, volume groups, and logical volumes, ensuring our configurations are repeatable and reliable. This approach not only saves time but also reduces the risk of human errors in managing critical storage resources.
For further reading and more complex scenarios, consider exploring additional Ansible modules and options, or integrating these tasks into larger automation workflows. Remember, automation is key to modern, efficient system administration in enterprise environments.