Syncing time is essential on Proxmox servers, especially in a cluster — time drift can cause serious issues with quorum, backups, and HA.

Here’s how to ensure accurate time sync on your Proxmox nodes:

✅ Recommended Method: Use systemd-timesyncd (built-in on Debian)

🔧 1. Enable and start time sync:

sudo timedatectl set-ntp true

Verify:

timedatectl status

Look for:

NTP service: active
System clock synchronized: yes

This uses systemd-timesyncd, which is light and reliable for Proxmox servers.

🧰 Alternative: Use chrony (Recommended for more control)

chrony is more robust, especially if your nodes might be offline/online often or you’re doing HA.

1. Install chrony:

sudo apt install chrony

2. Edit config (optional):

sudo nano /etc/chrony/chrony.conf

Add or edit NTP servers:

server time.google.com iburst
server 0.pool.ntp.org iburst
server 1.pool.ntp.org iburst

3. Restart and enable:

sudo systemctl enable chrony
sudo systemctl restart chrony

4. Check sync status:

chronyc tracking

🧪 Verify Time Sync on Proxmox

On each node:

timedatectl

All nodes should show:

• NTP service: active
• System clock synchronized: yes
• Same or very close times

🧠 Bonus: Sync RTC (hardware clock)

To sync system time to the hardware clock:

sudo hwclock --systohc

Let me know if you’re using a cluster and want to designate one Proxmox node as an NTP server for others, or if you’d like to sync from your Pi-hole box or router!

Perfect — turning one of your Proxmox nodes into an NTP server is a great idea for local time sync, especially in a cluster or if internet access is limited.

Here’s how to do it using chrony, which is ideal for Proxmox nodes:

🧭 Overview

• One Proxmox node will be the NTP server.
• The others will sync from it as NTP clients.

🖥️ On the Proxmox NTP Server (e.g., pve1)

1. Install chrony if not already installed:

sudo apt update
sudo apt install chrony

2. Edit the config to allow LAN clients

sudo nano /etc/chrony/chrony.conf

Add or uncomment these lines:

# Allow LAN subnet (adjust to your LAN range)
allow 192.168.1.0/24

# Make this machine act as an NTP server
local stratum 10

Optional: Use a known upstream NTP source for initial sync:

server time.google.com iburst
server 0.pool.ntp.org iburst

3. Restart chrony and enable it

sudo systemctl restart chrony
sudo systemctl enable chrony

🖥️ On the Proxmox Clients (e.g., pve2, pve3)

1. Install chrony:

sudo apt install chrony

2. Configure it to sync from the Proxmox NTP server:

sudo nano /etc/chrony/chrony.conf

Comment out existing server lines, and add:

server 192.168.1.10 iburst   # Replace with the IP of your Proxmox NTP server

3. Restart and enable:

sudo systemctl restart chrony
sudo systemctl enable chrony

4. Verify sync status:

chronyc sources
chronyc tracking

You should see something like:

Name/IP address             Stratum Poll Reach LastRx Last sample
===============================================================================
192.168.1.10                     10   6   377    32    -34us[ -44us] +/-  200us

🧪 Bonus: Test if the server is responding

From another node:

chronyc sources

Or:

ntpq -p 192.168.1.10

Let me know if you want to also allow the Pi-hole box or other clients on your LAN to sync from this NTP server too — it’s as easy as expanding the subnet in allow.