Teil 1: Erstellen der VM und Installieren von Debian 13

Objective of This Section

In this first part, we create a virtual machine in Proxmox and install a minimal Debian 13 system on it.

At the end of this section:

Debian is running successfully inside the VM
the system is accessible via console
we are ready for network, storage, and Nextcloud setup

Prerequisites

Hardware Recommendations

RAM: at least 4 GB (recommended: 8 GB)
System Disk: at least 32 GB (SSD/NVMe recommended)
Data Disk: separate HDD or SSD for Nextcloud data
CPU: 2–4 cores

VM Parameters (Example)

VM ID: 120
vCPUs: 4
RAM: 4 GB
Root Disk: 32 GB
Data Disk: 200 GB (later 250 GB)
Mount Target (later):
/srv/cloud.zn80.net/data

Note:
The data disk is not used during the Debian installation,
but will be mounted separately at a later stage.

Required Credentials (Example)

⚠️ Note:
In a production environment, use secure, unique passwords
and store them in a password manager.

root (VM)
ncadmin (VM)
Database User: nextcloud
Nextcloud Admin: nextcloud_admin

Debian Installation Medium

We use Debian 13 (amd64).

Download source (ISO): https://debian.snt.utwente.nl/debian-cd/13.3.0/amd64/iso-cd/

Step 1: Create the VM in Proxmox

Create a new VM
Assign the desired VM ID
Select the previously downloaded Debian ISO

Step 2: VM System Configuration

Machine Type and Agent

Machine: q35
→ modern CPU features such as improved PCIe, NVMe, and hardware emulation support
QEMU Guest Agent: enable
→ improved status reporting and clean shutdown functionality

Why q35 instead of i440fx:
The q35 machine type emulates a modern Intel chipset with native PCIe support. This enables proper PCIe passthrough (e.g., for GPUs or NVMe devices), AHCI controllers, and vIOMMU emulation. Compared to the legacy i440fx, it is significantly better suited for modern guest systems and extensions.

QEMU Guest Agent:
The QEMU Guest Agent is a small daemon running inside the guest system that enables direct communication with Proxmox. It allows clean shutdowns (instead of ACPI force-off), freezes file systems before snapshots/backups (ensuring consistency), and provides accurate status information such as IP addresses and memory usage.

Configure the System Disk

Disk Size: 32 GB
Cache: Default
Discard: Enable
(only relevant for SSD/NVMe)

Add Second Disk (Data)

We now add a second disk, which will later be used exclusively for Nextcloud data.

Size: e.g., 200 GB
Storage: according to your infrastructure
Discard: enable (for SSD/NVMe)

We deliberately start the data disk at 200 GB. It can later be expanded easily in Proxmox and within the guest system to demonstrate dynamic storage growth in a homelab environment.

CPU Configuration

Cores: 4
(2 are sufficient for small setups)
Type: host
→ exposes all CPU features to the VM

Why host:
The CPU type host passes all features and extensions of the physical host CPU (e.g., AVX, AES-NI) directly to the VM. This provides maximum performance. However, it is only recommended if you do not plan live migration between hosts with different CPU types, as this can cause migration failures.

Memory

Minimum: 2 GB (functional)
Recommended: 4 GB

Network

The default network configuration can remain unchanged.

Review Configuration

If everything is configured correctly, the VM summary should look similar to this.

Now start the VM and begin the Debian installation.

Step 3: Install Debian

Language & Region

To select Germany:

Other
Europe
Germany

The keyboard layout can then be accepted as proposed.

Hostname & Domain

Hostname: e.g., nc or cloud
Domain: either public or internal
(e.g., intranet.zuhause.de or example.org)

In this example, I chose:

cloud
zn80.net

Set Root Password

Assign a strong root password.

Since direct SSH login as root poses a security risk, we will disable this capability after installation.

Create a Regular User

In addition to the root user, we require a regular user account.
In this example, the username is ncadmin. Assign a strong password here as well.

Partitioning

Guided – use entire disk
Important: select the small 32 GB disk
(usually /dev/sda)
All files in one partition

Then write the changes to disk.

Partitioning Notes

During Debian installation, the commonly selected option is
“Guided – use entire disk.”

An alternative is:
“Guided – use entire disk and set up LVM.”

This creates Logical Volume Manager (LVM) volumes, allowing more flexible resizing of partitions (especially the root filesystem) later without repartitioning the disk.

Swap Area

Regardless of the partitioning method, a swap partition or swap file should be configured. In the screenshot above, a 1.8 GB swap partition is shown.

Typical guidelines:

At least 2–4 GB swap for low-RAM systems
For systems with ≤ 8 GB RAM, swap equal to RAM (1:1) is often recommended
With large amounts of RAM (> 16–32 GB), significantly less swap (2–8 GB) or a swap file is usually sufficient

Package Sources & Updates

Additional media: No
Debian mirror:
- Country: Germany
- Mirror: deb.debian.org
Proxy: No
Participate in package usage survey: No

Software Selection

We install no desktop environment.

❌ Debian Desktop Environment
❌ GNOME
✅ SSH Server

The web server will be installed manually later.

Bootloader

Install GRUB to: /dev/sda
(SCSI-0)

The Debian installation is now complete.

Step 4: Verify Boot Order

Remove the ISO from the VM’s CD/DVD drive and set the boot order to prioritize the hard disk. Otherwise, the VM may continuously attempt to boot from the empty ISO.

If the VM boots from the ISO again:

Power off the VM
Options → Boot Order
Move the system disk to the top
Move the ISO down or disable it

Boot order incorrect

Boot order correct

Result

If everything was completed correctly, you should now see the Debian 13 login console.

Next Step

Continue with:
Part 2: Configure IP, User Permissions, and Second Data Disk

Configure a static IP
Partition, format, and mount the second disk
Prepare the base system