Prerequisites
- 2 or more Proxmox VE hosts
- All hosts must be on the same version of Proxmox VE
- All hosts must be able to communicate over UDP ports 5404 and 5405 and TCP port 22
- Finalized hostnames and IP addresses (can't be changed later)
Preparation
- Log into the Proxmox web UI for each of the hosts to be joined to the cluster
- Run the following commands on each node to update them
# update software repositories
apt update
# install available updates
apt upgrade -y
Creating the Cluster
- On the main node of the cluster, select Datacenter from the left navigation menu
- Select Cluster from the left sub-navigation menu
- Click the Create Cluster button
- Give the cluster a name > Click Create
- Close the Create Cluster summary dialog
- Click the Join Information button
- Click the Copy Information button at the bottom of the dialog
- On the remaining nodes to join to the cluster, select Datacenter from the left navigation menu
- Select Cluster from the left sub-navigation menu
- Click the Join Cluster button
- Paste the copied join information into the Information field
- Enter the main node's root password in the password field
- Click the Join button
- After a few minutes the cluster nodes should sync and show data across all nodes
Further reading: https://pve.proxmox.com/pve-docs/pve-admin-guide.html#chapter_pvecm