How to create a network interface in Linux

Networking is an integral part of any Linux system. Allows communication between proper networking devices and the Internet. Servers must understand the network interface when setting up contact issues, solving contact issues, and managing device traffic flow.

A common problem in networking is losing contact after amending the network settings, which causes failure to access the system. This is usually due to poor understanding of incorrect configd IP address, wrong settings, and network interface compositions.

In this article, we will guide you by considering the best ways to understand the structures of these network interfaces, set up a network interface on Linux, check the available interface, create static and dynamic IP addresses, and consider the best ways to consider the network interface. At the end of this article, your network interface will have a solid foundation.

The table of content

What are the network interfaces?

A network interface is a connection point within the Linux system that allows to interact with other devices inside the network. That is, Linux connects the Colonel Network software side with the hardware side. The Linux systems provide many network interfaces that help facilitate communication between the system and other external networks.

Linux Linux Network interfaces of networking tasks defects, setting, management, and correction are required. Understanding what they are and how they work allows you to improve your server networking and security.

Types of network interface in Linux

The network interface can be classified in two main types: Physical and Virtual Network Interface.

Physical network interface

Physical network adaptors are components of network interface hardware that connect the system to the physical network. These physical networks include Wi -Fi and Ethernet. This adapter, commonly known as the Network Interface Cards (NIC), can be identified by their device names, such as Wlan0 and Eth0. These include the following:

1. Ethernet interface (ETH0, ETH1, and so on)

   The Ethernet interface is used for wired connection via Ethernet card and helps create high -speed networking. It can be used in data centers and servers.

2. Wi-FI interface (WLAN0, WLAN1, and so on)

   It represents the wireless network adapter, and it enables wireless contact through Wi-FI networks to servers.

Virtual Network Interface

Virtual network interface is software -based interfaces administered by the Linux operating system. They connect network virtualization technologies such as Dokar or KVM. There are many virtual network interfaces, and most common are included:

• Loopback interface: This is a special interface that allows the system to interact internally. It is permanently assigned to IP address 127.0.0.1, which is referred to as Local host.

• The bridge interface: They are used to connect multiple network interfaces. It is useful for virtualization environment (for example, Linux VM, Doker Networking).

• Tunnel interface: It is used for VPNS and networking tunnels. This helps to approve encrypted network traffic.

Why does the network interface important

The network interface creates an integral part of the Linux system. It enables communication between devices and the Internet, and properly forming these interfaces give the following benefits.

Smooth contact: Network interfaces allow devices to communicate on local networks and the Internet, which can enable the appropriate data exchange between servers and networks.

Proper network management: Administrator can create a network interface by making, managing and assigning, assigning and assigning traffic flow and improving traffic flow.

Better security: Administrator can create a network interface with firewalls and VPNs to secure data and prevent unauthorized access.

It provides support for virtualization and containerization: Virtual network interface provides appropriate communication between virtual machines, docar containers and other physical servers. This makes it necessary to create and manage the environment of the DOPs.

How to list the Network Interface in Linux

You can check the network interface available in the Linux environment using the following commands.

1. Using ip Order:

   All network interfaces and their status list l you, you can use ip link show Order. It shows details about a network interface such as name, status and Mac address.

2. Using ifconfig Order

   This command of all network interface, use this command: ifconfig -a. The command also shows details about the network interface and their current condition.

3. Using nmcli For a network manager’s control system

   To test all network interface status administered by the Network Manager, run:

   nmcli device status.

4. Using /sys/class/net/ Directory

   For all the interface list of network, run ls /sys/class/net/ This command is useful for scripting and automation as it provides a reliable way to check the interface available by the program.

How to create a network interface in Linux

Network interface is essential for the management of Linux servers and work stations. Understanding this layout will help ensure smooth communication in your system. This section will give you the right information about the creation of a network interface.

Assign static IP address

A stable IP address ensures that the device maintains the same IP after each reboot. This is especially useful for servers and devices that need permanent address. To assign static IP address, Network Manager Command Line Interface (nmcli) The command line provides utility as shown below.

nmcli connection modify eth0 ipv4.addresses 192.168.1.100/24   

nmcli connection modify eth0 ipv4.gateway 192.168.1.1          

nmcli connection modify eth0 ipv4.dns "8.8.8.8 8.8.4.4"        

nmcli connection modify eth0 ipv4.method manual                

nmcli connection up eth0                                       

These commands compiled a fixed IP, gateway, and DNS on ETH0, converted the interface into a manual format, and resumed it to implement new settings. Settings are maintained in reboot because they are stored NetworkManager

Assign temporary IP address

ip Command allows you to create a dynamically interface (not permanent on rebootes):

ip addr add 192.168.1.100/24 dev eth0     

ip route add default via 192.168.1.1      

These two orders give ETH0 IP 192.168.1.100/24 And all outbound traffic point to the gateway 192.168.1.1. Settings continue only until the next reboot or interface reset.

Assign IP Address with iFConfig (outdated)

The old systems are still shipped with ifconfig And route. These orders are also temporary.

ifconfig eth0 192.168.1.100 netmask 255.255.255.0 up  

route add default gw 192.168.1.1 eth0                

Note: Prefer ip Or nmcli On modern systems.

Enable DHCP with NMCLI

The address assigned to a DHCP automatically gives the Network an IP address.

nmcli connection modify eth0 ipv4.method auto   

nmcli connection up eth0                        

To renew or request direct leases:

dhclient eth0   

These commands fixed the ETH0 to use the DHCP, re -start the link so that the change is implemented, and trigger the quick lease renewal (optionally).

Assign multiple IP addresses in an interface

A network interface can be assigned to several addresses, which applies to host a number of services on the same interface.

Using an IP command (temporary assignment)

ip addr add 192.168.1.101/24 dev eth0   

ip addr add 2001:db8::1/64 dev eth0     

These two commands connect an additional IPV4 and IPV6 address to ETH0 until the interface is reset or restart the system

Permanent layout (net plan)

Edit /etc/netplan/01-netcfg.yaml File:

network:

  version: 2

  renderer: networkd

  ethernets:

    eth0:

      addresses:

        - 192.168.1.100/24

        - 192.168.1.101/24

        - 2001:db8::1/64

After the file edit, run away sudo netplan apply Extra leaves to stay across the ribbottos.

How to configure the Network Bridge in Linux

A network bridge allows multiple interfaces to operate as the same network class, which is useful in virtualization (KVM, Doker).

Using brctl (Bridge Uttals Package)

brctl addbr br0                       

brctl addif br0 eth0                  

ip addr add 192.168.1.100/24 dev br0  

ip link set br0 up                    

These commands make the BRG BR0, connect ETH0 to it, give the bridge their IP, and bring it online.

Using NMCLI (for Network Manager -administered systems)

nmcli connection add type bridge ifname br0                       

nmcli connection modify br0 bridge.stp no                         

nmcli connection add type bridge-slave ifname eth0 master br0     

nmcli connection up br0                                           

This sequence builds the same bridge through a network manager, disabled STP Fastest harmony connects ET, ETH 0 as a slave, and activates the bridge to reach the guest network.

Best process for creating a network interface in Linux

Make your structures permanent

One of the network engineers makes errors in Linux networking that are making changes that do not last after re -running. Although specific commands can temporarily edit network settings, they do not permanently save these changes.

To ensure that these network settings avoid server reboot, edit system configuration files such as /etc/network/interfaces. Once you make sure that all changes are permanent, there will be no unexpected obstacles when a system resumes.

Assign static IPS for servers

Stable IP addresses are perfect for servers and critical infrastructure. Unlike the DHCP address, which can change over time, static IP leaves are more stable and reliable. For services like web hosting and database management, static IP play a key role, as IP addresses do not need to be changed.

Save your network interface

The network interface has entry points in a system, so if they have been wrongly confirmed, they may be at a considerable risk of security. To reduce attacks, organizers should close all unused network interfaces by editing the configuration file to prevent automatic activation. In addition, you should use firewall tools to control traffic that tries to reach the system.

Monitor your network interface

As a system administrator, monitoring the network interface helps prevent time time and ensure proper network reliability. You can check your network interface status by running commands link show Or if-config -a. You can also monitor them in real time using tools such as Net Stat. Monitoring your system ensures that network issues are quickly known, reduced time and improve network stability.

Constantly update network packages

You need to update network management tools and drivers permanently as it helps implement security patch and other performance improvements, as outdated network package can cause security risks. Have specific packages related to the network such as network-managerFor, for, for,. bridge-utils And iproute2.

Conclusion

The establishment of a network interface in Linux is a basic skill that every system administrator should have. Whether you create static IP addresses or activate DHCP, understanding these concepts will ensure that your systems are stable and in proper contact. Implementing excellent methods such as traffic monitoring and saving network interface gives you the best results. When you continue to work with Linux, you can experience different settings to deepen your understanding of the network interface.