Clustering

A Proxmox cluster groups multiple Proxmox nodes together, enabling centralized management, live migration (moving VMs between nodes), and high availability. When second node is connected to a cluster, it will assume primary cluster roles and authentication. 
 Pre Requisites: 
 
 All nodes must be running the same or compatible version of Proxmox VE 
 All nodes must be able to communicate over the network (low latency preferred) 
 Odd number of nodes recommended (3+) for quorum 
 Shared storage is recommended (but not required for basic clustering) for High Availability 
 
 Note : Creating a cluster on an existing node will reset some configurations. Set up clustering before deploying production VMs. 
   
 Creating the Cluster on Primary Node 
 
 On the primary node, go to Datacenter > Cluster 
 Click Create Cluster 
 Enter a Cluster Name (e.g., homelab-cluster) 
 Set the Cluster Network (the network ring used for cluster communication) 
 Click Create 
 Click Join Information and copy the join token 
 
   
 Adding Additional Nodes 
 
 Log into the second Proxmox node's web console 
 Go to Datacenter > Cluster 
 Click Join Cluster 
 Paste the join information from the first node 
 Enter the root password of the first node when prompted 
 Click Join — the node joins the cluster 
 
 Afterr joining, all nodes appear in the left panel of any node's web console. You can manage all VMs and containers across all nodes from a single interface. 
   
 Live Migration 
 
 Right-click a VM on any node 
 Select Migrate 
 Choose the target node 
 Click Migrate — the VM moves to the other node (live, with minimal interruption if using shared storage)