Building KVM on Debian Linux as a Foundation for Experiments

Ameni Nuretemo — Wed, 11 Mar 2026 10:20:56 +0000

Hi everyone. I'm building a "Home Lab" for my technical experiments. In this post, I'll share how to configure KVM and network bridging on Debian 13.

Configuration

Operating System: Debian GNU/Linux 13
Processor: 16 × AMD Ryzen 7 7700 8-Core Processor
Memory: 32 GiB of RAM
Graphics Processor: NVIDIA GeForce RTX 3050/PCIe/SSE2
Storage: 2TB SSD
Manufacturer: Micro-Star International Co., Ltd.
Product Name: MS-7E80

Verifying Virtualization

Virtualization requires specific CPU features. Please ensure they are enabled in your BIOS.

For Intel:

Intel VT-x
Intel Virtualization Technology

For AMD:

SVM
AMD-V

Set these to Enabled.

Confirm that SVM Mode is Enabled in the BIOS. To verify this within Linux, run:

egrep -c '(vmx|svm)' /proc/cpuinfo

Since I am using an AMD processor, a value of 1 or higher indicates virtualization is supported. In my case, it returned 16, which corresponds to the number of available logical CPUs.

Setting the Working Directory

I have established a rule to create a vm directory in the $HOME folder to house all virtual machines.

mkdir ~/vm

Installing KVM + libvirt (The Standard Linux Approach)

Install KVM and the related libvirt packages:

sudo apt install qemu-kvm libvirt-daemon-system virt-manager
sudo adduser $USER libvirt

Note: Since I added myself to the libvirt group, a logout and login are required for the changes to take effect.

The virtualization environment is now ready.

Additional Installations

While not strictly required, I am also installing bridge utilities and tools for creating virtual machines via the command line:

sudo apt install bridge-utils virtinst

Testing

Let's create the first virtual machine. Download the Debian ISO from debian.org, create an iso folder within the vm directory, and store it there.

cd ~/vm
mkdir ./iso
mv ~/Downloads/debian-13.3.0-amd64-netinst.iso ~/vm/iso

Setting Up the Network Bridge

We will configure a network bridge to simplify communication and management between servers.

Procedure Workflow:

Create a bridge interface.
Connect the physical NIC to the bridge.
Migrate the IP configuration to the bridge.
Restart the connection.

Verifying Network Status

Check the status of NetworkManager with the following command:

systemctl status NetworkManager

If it is active, check the IP status:

ip a

Your physical interface (e.g., enp****) will be displayed. We will convert this into a bridge.

1. Create the Bridge

sudo nmcli connection add type bridge ifname br0 con-name br0

2. Connect Physical NIC to the Bridge

sudo nmcli connection add type bridge-slave ifname enp**** master br0
sudo nmcli connection up bridge-slave-enp****
sudo nmcli connection up br0

3. Set the IP on the Bridge
I will reuse the current IP: 192.168.0.200/24.

Configuration:

sudo nmcli connection modify br0 ipv4.addresses 192.168.0.200/24
sudo nmcli connection modify br0 ipv4.gateway 192.168.0.1
sudo nmcli connection modify br0 ipv4.method manual

DNS:

sudo nmcli connection modify br0 ipv4.dns 192.168.0.1

4. Disable the Original Connection

sudo nmcli connection down enp****

5. Activate the Bridge

sudo nmcli connection up br0

Success Verification:
Run ip a. You should see br0 with the IP 192.168.0.200 and your physical NIC (e.g., enp11s0) listed with master br0.

Once this is complete, you can select network source = br0 when creating a VM in KVM, allowing the VM to obtain an IP (e.g., 192.168.0.x) directly on the local network.

Creating a VM

Launch the Virtual Machine Manager.

Allocate Memory and CPU.

Specify the Storage location (within the `vm` folder).

Specify the ISO image location.

Perform the Final Review and start the installation.

Installation Complete

The OS installation will now proceed.

Easily Build Your Own Private Cloud Storage with Nextcloud and Docker

Ameni Nuretemo — Mon, 09 Mar 2026 20:46:15 +0000

1. Introduction

Why build your own?
Storing large amounts of data on public cloud services can be expensive.
I wanted to set up my own storage server in a local environment to save costs.
Why Nextcloud + Docker?
Ease of Setup: Get up and running quickly.
Simple Maintenance: Easy to update and manage containers.

2. Environment

OS: Debian Linux
Prerequisites: A system where Docker and Docker Compose can be installed.

3. Step-by-Step Guide

Install Docker

sudo apt install docker.io docker-compose-plugin

Create a Working Directory

mkdir nextcloud
cd nextcloud

Create `docker-compose.yml`

nano docker-compose.yml

services:

db:
    image: mariadb:10.11
    restart: always
    command: --transaction-isolation=READ-COMMITTED --binlog-format=ROW
    volumes:
      - nextcloud_db:/var/lib/mysql
    environment:
      MYSQL_ROOT_PASSWORD: ${MYSQL_ROOT_PASSWORD}
      MYSQL_PASSWORD: ${MYSQL_PASSWORD}
      MYSQL_DATABASE: ${MYSQL_DATABASE}
      MYSQL_USER: ${MYSQL_USER}

app:
    image: nextcloud:apache
    restart: always
    ports:
      - 8080:80
    depends_on:
      - db
    volumes:
      - nextcloud_data:/var/www/html
    environment:
      MYSQL_HOST: db
      MYSQL_DATABASE: ${MYSQL_DATABASE}
      MYSQL_USER: ${MYSQL_USER}
      MYSQL_PASSWORD: ${MYSQL_PASSWORD}

    volumes:
      nextcloud_db:
      nextcloud_data:

Create .env file

nano .env

MYSQL_ROOT_PASSWORD=change-me
MYSQL_PASSWORD=change-me
MYSQL_DATABASE=nextcloud
MYSQL_USER=nextcloud

Launch Containers

docker compose up -d

4. Post-Installation & Operation

Initial Setup via Browser
Access http://localhost:8080 and create an admin account.
Tip: Most DB settings from your .env file will be auto-filled. Just double-check them!
Useful Commands
Status check, Update, Start/Stop, and Logs.

5. Conclusion & Security

Personal Reflection: Using Docker makes maintenance incredibly easy.
Important Security Note: This setup is not encrypted (No SSL). If you plan to access it from the internet, please use a Reverse Proxy or a tool like Tailscale.

Forem: Ameni Nuretemo