A cluster is nothing but a group of Proxmox servers or nodes, sharing resources. A Proxmox cluster can contain up to 32 physical nodes. If network latency permits, the number of nodes can be higher. But any number of nodes higher than 32 may cause an unstable situation within the cluster.
As of Proxmox VE 5, we cannot create clusters through the graphical interface. The entire process of cluster creation must be done through the CLI. Proxmox provides a tool to create and add nodes to a cluster called Proxmox VE Cluster Manager or pvecm.
When naming a cluster, keep in mind that it can be a maximum of 15 characters and only—can be used as a special character.
To create a new cluster, log in to any available Proxmox node through SSH and run the following command:
# pvecm create <clustername>
For our first demo cluster, we are going to run the...