Setting up a network interface with a static address in Debian distributions

To set up a network interface with a static address in Debian, modify the configuration file /etc/network/interfaces. Here are the steps to follow.

Open a terminal and edit the /etc/network/interfaces file using a text editor such as nano or vim. Here is an example of using nano:

sudo nano /etc/network/interfaces

Add the configuration for the network interface in the file. Below is an example for interface eth0, which will get the IP address 192.168.1.100 with a subnet mask of 255.255.255.0 and a default gateway of 192.168.1.1.

# Ustawienia interfejsu Ethernet
auto eth0
iface eth0 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

Parameters

  
- address: The actual static IP address you want to assign to the interface.
- netmask: The subnet mask that is used for the local network.
- gateway: The IP address of the gateway (router) through which communication with other networks takes place.
- dns-nameservers: The addresses of the DNS servers that will be used for name resolution.
  

If you are using nano, press CTRL + X, then Y and Enter to save your changes and exit the editor.

To apply the new settings, restart the web interface. Use the following command:

sudo ifdown eth0 && sudo ifup eth0

If you are using a system where ifupdown can only be handled by systemd, you can also use:

sudo systemctl restart networking

To ensure that the interface has been successfully configured, use the command:

ip a

This command will display the configurations of all interfaces, including the assigned IP address.

By setting a network interface statically, you ensure that it will always have the same IP address, which is particularly useful for servers and systems that require stability in network communication.

Correct configuration of the DNS (Domain Name System) is essential for proper use of the Internet. To do this, you need to edit the two main configuration files:

/etc/host.conf: Defines how the name resolution function works.

Example file contents:

    order hosts,bind
    multi on

Sets that local host files will be searched first, followed by remote DNS servers.

/etc/resolv.conf: Contains the addresses of the DNS servers that will be used to resolve domain names.

Example of file:

    nameserver 8.8.8.8
    nameserver 8.8.4.4

This sets Google's DNS servers as default.

Netplan is a network configuration tool for Ubuntu systems, introduced in versions 17.10 and later. It allows simple configuration of network interfaces and their settings.

The netplan configuration is stored in YAML files in the /etc/netplan/ directory. They can be edited with a text editor, such as:

    sudo nano /etc/netplan/01-netcfg.yaml

Example file content for a static IP address:

    network:
      version: 2
      ethernets:
        eth0:
          addresses:
            - 192.168.1.100/24
          gateway4: 192.168.1.1
          nameservers:
            addresses:
              - 8.8.8.8
              - 8.8.4.4

After editing the file, save the changes and exit. Then примените the configuration using the command:

    sudo netplan apply

To ensure that the network interface is configured correctly, use:

    ip a

• YAML format: Remember to use correct YAML formatting, especially with regard to indentation.
• Debugging: In case of errors, you can use the sudo netplan try command, which allows you to test your changes before applying them permanently.

Netplan simplifies network configuration in Ubuntu by offering a flexible approach to connection management.