Install Proxmox VE on Debian 11 Bullseye

Introduction

The installation of a supported Proxmox VE server should be done via bare-metal ISO installer. In some cases it makes sense to install Proxmox VE on top of a running Debian Bullseye 64-bit, especially if you want a custom partition layout. For this How-To any official Bullseye installation medium should work.

Install a standard Debian Bullseye (amd64)

Install a standard Debian Bullseye, for details consider the Debian installation guide, and configure a static IP. It is recommended to only install the "standard system utilities" and "SSH server" package selection, as Proxmox VE brings its own packages for QEMU and LXC. A desktop environment is not necessary.

Add an /etc/hosts entry for your IP address

The hostname of your machine must be resolvable via /etc/hosts. This means that in /etc/hosts you need one of the following entries for your hostname:

1 IPv4 or
1 IPv6 or
1 IPv4 and 1 IPv6

Note: This also means removing the address 127.0.1.1 that is present as default.

For instance, if your IP address is 192.168.15.77, and your hostname prox4m1, then your /etc/hosts file could look like:

127.0.0.1       localhost
192.168.15.77   prox4m1.proxmox.com prox4m1

# The following lines are desirable for IPv6 capable hosts
::1     localhost ip6-localhost ip6-loopback
ff02::1 ip6-allnodes
ff02::2 ip6-allrouters

You can test if your setup is ok using the hostname command:

hostname --ip-address
192.168.15.77 # should return your IP address here

Install Proxmox VE

Adapt your sources.list

Add the Proxmox VE repository:

echo "deb [arch=amd64] http://download.proxmox.com/debian/pve bullseye pve-no-subscription" > /etc/apt/sources.list.d/pve-install-repo.list

Add the Proxmox VE repository key as root (or use sudo):

wget https://enterprise.proxmox.com/debian/proxmox-release-bullseye.gpg -O /etc/apt/trusted.gpg.d/proxmox-release-bullseye.gpg 
# verify
sha512sum /etc/apt/trusted.gpg.d/proxmox-release-bullseye.gpg 
7fb03ec8a1675723d2853b84aa4fdb49a46a3bb72b9951361488bfd19b29aab0a789a4f8c7406e71a69aabbc727c936d3549731c4659ffa1a08f44db8fdcebfa  /etc/apt/trusted.gpg.d/proxmox-release-bullseye.gpg

Update your repository and system by running:

apt update && apt full-upgrade

Install the Proxmox VE Kernel

First you need to install and boot the Proxmox VE kernel, as some packages depend on specific kernel compile flags to be set or feature extensions (e.g., for apparmor) to be available.

apt install pve-kernel-5.15

systemctl reboot

Note that while the pve-kernel-5.15 is the default stable kernel for the Proxmox VE 7.x series, there's also a newer opt-in kernel available with pve-kernel-5.19, possibly helping to resolve some hardware related woes on modern systems.

Install the Proxmox VE packages

apt install proxmox-ve postfix open-iscsi

Configure packages which require user input on installation according to your needs.

If you have a mail server in your network, you should configure postfix as a satellite system. Your existing mail server will then be the relay host which will route the emails sent by Proxmox VE to their final recipient. If you don't know what to enter here, choose local only and leave the system name as is.

Remove the Debian Kernel

Proxmox VE ships its own kernel and keeping the Debian default kernel can lead to trouble on upgrades, for example, with Debian point releases. Therefore, you must remove the default Debian kernel:

apt remove linux-image-amd64 'linux-image-5.10*'

Update and check grub2 config by running:

update-grub

Recommended: Remove the os-prober Package

The os-prober package scans all the partitions of your host to create dual-boot GRUB entries. But the scanned partitions can also include those assigned to virtual machines, which one doesn't want to add as boot entry.

If you didn't install Proxmox VE as dual boot beside another OS, you can safely remove the os-prober package:

apt remove os-prober

Connect to the Proxmox VE web interface

Connect to the admin web interface (https://your-ip-address:8006). If you have a fresh install and have not added any users yet, you should select PAM authentication realm and login with root user account.

Create a Linux Bridge

Once logged in, create a Linux Bridge called vmbr0, and add your first network interface to it.

Upload Subscription Key

The Proxmox VE enterprise repository is set up automatically during the installation as it's the recommended repository for stable, enterprise usage. Access to that repository is one of the benefits of a Proxmox VE subscription, see this forum thread for more info about why you should get one.

You should upload your subscription key now in the web interface, then you can remove the no-subscription repository added for installation.

rm /etc/apt/sources.list.d/pve-install-repo.list

Troubleshooting

resolv.conf gets overwritten

The PVE GUI expects to control DNS management and will no longer take its DNS settings from /etc/network/interfaces. Any package that auto-generates (overwrites) /etc/resolv.conf will cause DNS to fail, e.g. packages 'resolvconf' for IPv4 and 'rdnssd' for IPv6.

ipcc_send_rec[1] failed

If you see

ipcc_send_rec[1] failed: Connection refused

then you should review your /etc/hosts file according to the instructions above.