How to Configure Network Settings During Debian 12 Bookworm Installation

Introduction

Debian 12 “Bookworm” is a stable and powerful Linux distribution widely used for servers, desktops, and embedded systems. Proper network configuration during installation ensures smooth internet connectivity, access to repositories, and remote management capabilities. This guide walks you through configuring network settings during the installation process, covering both graphical and text-based installation methods.

1. Understanding Network Configuration Options

During installation, Debian allows you to configure networking in several ways:

• DHCP (Dynamic Host Configuration Protocol) – The system automatically obtains an IP address from a DHCP server.
• Static IP Configuration – Manually defining an IP address, subnet mask, gateway, and DNS settings.
• Wireless Configuration – Setting up Wi-Fi by selecting an access point and providing authentication details.
• Skipping Network Configuration – This can be done if network settings will be configured later.

2. Configuring Network Settings in Graphical Installer

Step 1: Boot the Installer

1. Download the Debian 12 ISO from the official Debian website.
2. Create a bootable USB using a tool like Rufus (Windows) or dd (Linux/macOS).
3. Boot the system from the USB and select Graphical Install from the boot menu.

Step 2: Select Network Configuration Mode

After choosing the installation language, location, and keyboard layout, you’ll reach the Configure the Network screen.

• If a wired connection with DHCP is available, Debian will automatically detect and configure it.
• If you need to set a static IP, select Manual Configuration and enter the required details:
  • IP Address (e.g., 192.168.1.100)
  • Subnet Mask (e.g., 255.255.255.0)
  • Gateway (e.g., 192.168.1.1)
  • DNS Server(s) (e.g., 8.8.8.8 for Google DNS)

Step 3: Configuring Wi-Fi (If Applicable)

If you are using a wireless network:

1. Choose your Wi-Fi network (SSID) from the list.
2. Enter the Wi-Fi password to establish a connection.

Step 4: Setting the Hostname and Domain Name

1. Enter a hostname (e.g., debian-server).
2. (Optional) Enter a domain name if you are setting up a network with a domain (e.g., example.com).

3. Configuring Network Settings in Text-Based Installer

If you choose the Text Mode Installer, follow these steps:

Step 1: Choose Network Configuration

Once you reach the network configuration screen:

• For DHCP: Select Auto-configure with DHCP.
• For Static IP: Select Configure manually, then enter:
  • IP Address
  • Netmask
  • Gateway
  • DNS Server(s)

Step 2: Wi-Fi Setup

If you are using a wireless network, Debian will prompt you to:

• Select a Wi-Fi network.
• Enter the Wi-Fi security key.

Step 3: Set Hostname and Domain

1. Enter your desired hostname.
2. If applicable, enter a domain name.

4. Post-Installation Network Configuration

If you skipped network configuration or need to modify settings later, follow these steps:

Checking Network Interfaces

Run the following command to check available network interfaces:

ip a

or

ifconfig -a

Configuring Static IP Address

Edit the network configuration file:

sudo nano /etc/network/interfaces

Example static IP configuration:

iface enp0s3 inet static
    address 192.168.1.100
    netmask 255.255.255.0
    gateway 192.168.1.1
    dns-nameservers 8.8.8.8 8.8.4.4

Save and apply changes:

sudo systemctl restart networking

Configuring NetworkManager (For GUI Systems)

For desktop environments using NetworkManager:

1. Open Settings → Network.
2. Select your connection.
3. Modify IPv4 settings to Manual and enter the static IP details.

5. Troubleshooting Network Issues

Check Network Connectivity

ping 8.8.8.8

If there is no response, check your configuration.

Restart Networking Service

sudo systemctl restart networking

View Logs for Errors

journalctl -xe | grep network

Renew DHCP Lease

sudo dhclient -r && sudo dhclient

Conclusion

Properly configuring network settings during Debian 12 installation ensures a stable and functional system. Whether using DHCP or static IP, understanding these settings helps prevent connectivity issues and enhances system reliability. By following this guide, you should have a smooth network setup process during and after installation.