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Proxmox VE 9 Three-Node Cluster Setup Guide

This guide replicates what the Proxmox VE Helper Scripts post-install script does, but manually via CLI so each step is understood. Then it covers setting up a 3-node cluster.

Proxmox VE 9 Three-Node Cluster Setup Guide

Manual Post-Install Configuration & Cluster Setup via CLI

This guide replicates what the Proxmox VE Helper Scripts post-install script does, but manually via CLI so each step is understood. Then it covers setting up a 3-node cluster.

Prerequisites

  • 3 Proxmox VE 9.0.x nodes freshly installed
  • Network connectivity between all nodes
  • SSH access to all nodes
  • Static IP addresses configured on all nodes

My Node Configuration

This guide will be based on my node configuration

Node 1 (ceres): IP=192.168.10.10
Node 2 (eros):  IP=192.168.10.11  
Node 3 (tyco):  IP=192.168.10.12

Part 1: Post-Install Configuration (Perform on ALL Nodes)

These steps replicate exactly what the helper script does, nothing more.

Step 1: Configure APT Repositories

Proxmox 9 uses the newer deb822 format for repositories.

1.1 Remove Enterprise Repositories

Check if enterprise repository exists and comment it out:

if grep -q "Components:.*pve-enterprise" /etc/apt/sources.list.d/*.sources 2>/dev/null; then
    for file in /etc/apt/sources.list.d/*.sources; do
        if grep -q "Components:.*pve-enterprise" "$file"; then
            sed -i '/^\s*Types:/,/^$/s/^\([^#].*\)$/# \1/' "$file"
        fi
    done
fi

1.2 Configure Debian Base Repositories

Create deb822 format Debian sources:

cat > /etc/apt/sources.list.d/debian.sources <<EOF
Types: deb
URIs: http://deb.debian.org/debian
Suites: trixie
Components: main contrib
Signed-By: /usr/share/keyrings/debian-archive-keyring.gpg
 
Types: deb
URIs: http://security.debian.org/debian-security
Suites: trixie-security
Components: main contrib
Signed-By: /usr/share/keyrings/debian-archive-keyring.gpg
 
Types: deb
URIs: http://deb.debian.org/debian
Suites: trixie-updates
Components: main contrib
Signed-By: /usr/share/keyrings/debian-archive-keyring.gpg
EOF

1.3 Add No-Subscription Repository

Add the free Proxmox repository:

cat > /etc/apt/sources.list.d/proxmox.sources <<EOF
Types: deb
URIs: http://download.proxmox.com/debian/pve
Suites: trixie
Components: pve-no-subscription
Signed-By: /usr/share/keyrings/proxmox-archive-keyring.gpg
EOF

1.4 Add Ceph Repository (Disabled since you don't need it)

Create disabled Ceph repository file (no subscription). Remove the # symbols if you want to enable. Another option is to add an "Enabled:" field with "yes" for enabled or "no" for disabled. This is the new deb822 method and probably the better way.

cat > /etc/apt/sources.list.d/ceph.sources <<EOF
# Types: deb
# URIs: http://download.proxmox.com/debian/ceph-squid
# Suites: trixie
# Components: no-subscription
# Signed-By: /usr/share/keyrings/proxmox-archive-keyring.gpg
EOF

Create disabled Ceph enterprise repository (requires subscription):

cat > /etc/apt/sources.list.d/ceph-enterprise.sources <<EOF
# Disabled - requires subscription
# Types: deb
# URIs: https://enterprise.proxmox.com/debian/ceph-squid
# Suites: trixie
# Components: enterprise
# Signed-By: /usr/share/keyrings/proxmox-archive-keyring.gpg
EOF

1.5 Add PVE Test Repository (Disabled)

Create disabled pvetest repository for future use. Remove the # symbols if you want to enable:

cat > /etc/apt/sources.list.d/pve-test.sources <<EOF
# Types: deb
# URIs: http://download.proxmox.com/debian/pve
# Suites: trixie
# Components: pve-test
# Signed-By: /usr/share/keyrings/proxmox-archive-keyring.gpg
EOF

Step 2: Disable Subscription Nag

This removes the popup reminder about subscriptions when logging into the web interface.

Create APT hook to automatically patch the subscription check:

cat > /etc/apt/apt.conf.d/no-nag-script <<'EOF'
DPkg::Post-Invoke { "if [ -s /usr/share/javascript/proxmox-widget-toolkit/proxmoxlib.js ] && ! grep -q -F 'NoMoreNagging' /usr/share/javascript/proxmox-widget-toolkit/proxmoxlib.js; then echo 'Removing subscription nag from UI...'; sed -i '/data\.status/{s/\!//;s/active/NoMoreNagging/}' /usr/share/javascript/proxmox-widget-toolkit/proxmoxlib.js; fi"; };
EOF

Reinstall widget toolkit to apply the change:

apt --reinstall install -y proxmox-widget-toolkit

Note: Clear your browser cache after this change (Ctrl+Shift+R).

Step 3: Disable High Availability Services (Since Not Using HA)

The helper script offers to disable HA services if you're not using them.

Disable Local Resource Manager:

systemctl disable --now pve-ha-lrm

Disable Cluster Resource Manager:

systemctl disable --now pve-ha-crm

Important: Keep corosync enabled as it's needed for cluster communication. Do not disable corosync.

Step 4: Update the System

Update package lists:

apt update

Perform full system upgrade:

apt dist-upgrade -y

Step 5: Reboot (Recommended)

The helper script recommends a reboot after these changes:

reboot

Wait for the node to come back online before proceeding to the next node.

Part 2: Create the Cluster

The helper script doesn't handle cluster creation - this is a separate process. Here's how to set up a 3-node cluster. The steps are the same for any cluster size, but in this example it will be a 3-node cluster.

Step 6: Initialize the Cluster (On First Node Only - ceres)

Create cluster with a meaningful name:

pvecm create homelab-cluster

Verify cluster status:

pvecm status

The output should show:

  • Cluster name: homelab-cluster
  • Nodes: 1
  • Quorum: 1

Step 7: Join Additional Nodes to Cluster

On the second node (eros):

Join the cluster using IP of first node (you'll be prompted for the root password of the first node):

pvecm add 192.168.10.10

On the third node (tyco):

Join the cluster using IP of first node (you'll be prompted for the root password of the first node):

pvecm add 192.168.10.10

Step 8: Verify Cluster Formation

On any node, verify all nodes have joined.

Check cluster status:

pvecm status

List all nodes:

pvecm nodes

Check Corosync status (should be active):

systemctl status corosync

Expected output should show:

  • 3 nodes online
  • Quorum established (with 3 votes)
  • All nodes with "online" status

Important Notes

Browser Cache

After completing the post-install steps, clear your browser cache:

  • Chrome/Firefox: Ctrl+Shift+R or Ctrl+F5
  • This ensures the subscription nag removal takes effect

Apply to All Nodes

The post-install steps (Part 1) must be performed on ALL nodes in the cluster individually.

Cluster Considerations

  • Corosync remains enabled for cluster communication (even with HA disabled)
  • You can migrate VMs/containers between nodes if using shared storage
  • The cluster provides centralized management through any node's web interface

Summary

This guide covered:

  • Post-Install Steps (exactly what the helper script does):
    • Configure APT repositories (switch to no-subscription)
    • Disable subscription nag
    • Disable HA services (since not needed)
    • System update
    • Reboot
  • Cluster Creation:
    • Initialize cluster on first node
    • Join additional nodes
    • Verify cluster status

Your 3-node Proxmox cluster is now configured and ready for use without unnecessary overhead from enterprise features or high availability services you don't need.

Related Content

Proxmox VE 9 Post-Install Setup Guide (2026)

Proxmox VE 9 Post-Install Setup Guide (2026)

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