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• observers: Set of hosts to observe the cluster (only the first is considering)

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• Hypervisors: Set of machines to hosts VMs.

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Node redundancy

All nodes in the cluster have an access to a shared storage via ceph (more details heresee Shared storage section). With it, the cluster is in N to N redundancy mode.

• Corosync will provides messaging and membership services.
• Pacemaker will manage the cluster (synchronize resources between each node).

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More details on pacemaker here and corosync here.

libvirt

To use pacemaker like

Management tool

The vm_manager project is an high-level interface of pacemaker and ceph to manage the VM like a resource. He is installed during the installation step and provides the vm-mgr command.

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• Undefined:
• Disabled:
• Failed:
• Started:
• Starting:
• Stopping:
• Stopped:

Manage VM

• Add VM in the cluster:

  Code Block
  language bash
  vm-mgr create --name NAME --xml /path/to/configuration.xml --image /path/to/disk.qcow2 --disable --force --enable-live-migration --migration-user virtu --migrate-to-timeout 180

  Check the execution of the resource:

  Code Block
  language bash
  crm status

  Get the status of the resource:

  Code Block
  language bash
  vm-mgr status --name NAME

  Delete VM in the cluster:

  Code Block

  language	bash

  vm-mgr remove --name NAME