ha-cluster-pacemaker

This guide helps you set up and manage a basic Pacemaker cluster on various Linux systems like CentOS, AlmaLinux, Rocky Linux, and Fedora.

What This Role Can Do

• Enable necessary system repositories
• Install required packages
• Create users and groups for the Pacemaker cluster
• Set up the firewall
• Generate entries in /etc/hosts
• Authorize cluster nodes
• Create or expand a cluster (check allow_cluster_expansion)
  • Needs at least 2 nodes to start
  • Supports a single heartbeat with up to 8 links
  • Can involve remote nodes
  • Works with automatic or custom interfaces/IPs for heartbeat
• Start the cluster on boot
• Configure STONITH devices (fencing)
  • Installs fence_xvm by default
  • Optional configurations for fence_kdump, fence_vmware, and fence_aws

This role supports a --check mode for the default configuration and partially for other options.

Reporting Issues

If you encounter a problem, please provide:

• Ansible version used
• Operating System running Ansible
• Playbook and inventory file that caused the error (remove sensitive info)
• Error message or issue description

Requirements

• Depends on the role: ondrejhome.pcs-modules-2.
• Ansible version 2.8 or later (older versions may work but are not guaranteed).
• For RHEL 6/7/8, machines must be registered. Access to 'High Availability' or 'Resilient Storage' repositories is enabled by default.

Role Variables

• Define user for cluster nodes authorization:

  cluster_user: 'hacluster'
  

• Define password for the cluster user:

  cluster_user_pass: 'testtest'
  

• Define the cluster name:

  cluster_name: 'pacemaker'
  

• Enable firewall configuration:

  cluster_firewall: true
  

• Enable cluster to start on boot:

  cluster_enable_service: true
  

Fencing Device Configurations

• Set options for configuring fencing devices like fence_xvm, fence_vmware, or fence_aws.
• Choose how to map fencing devices to nodes, either one device per node or one device per cluster.

Security Recommendations

• Always update cluster_user_pass to a secure value.
• Use ansible-vault to encrypt sensitive variables. Create a separate file for these variables, then encrypt and include it in your playbook.

Example Playbooks

1. Create a basic cluster:

   - hosts: cluster
     roles:
        - { role: 'ondrejhome.ha-cluster-pacemaker', cluster_name: 'test-cluster' }
   

2. Create a cluster without the firewall:

   - hosts: cluster
     roles:
        - { role: 'ondrejhome.ha-cluster-pacemaker', cluster_name: 'test-cluster', cluster_firewall: false }
   

Inventory File Examples

Define your cluster nodes in an inventory file for proper configuration. Here’s a basic example for CentOS/RHEL:

[cluster]
192.168.22.21 vm_name=fastvm-centos-7
192.168.22.22 vm_name=fastvm-centos-7

License

This role is licensed under GPLv3.

Author Information

For inquiries or issues, contact the author at ondrej-xa2iel8u@famera.cz or raise an issue on GitHub.