Got Ethernet to have an IP address

If you are using an ethernet cable and are not connected to the network at this point you may need to run:

sudo dhclient eth0

so now I can see:

ip address
1: lo: <LOOPBACK,UP,LOWER_UP> mtu 65536 qdisc noqueue state UNKNOWN group default qlen 1000
    link/loopback 00:00:00:00:00:00 brd 00:00:00:00:00:00
    inet 127.0.0.1/8 scope host lo
       valid_lft forever preferred_lft forever
    inet6 ::1/128 scope host
       valid_lft forever preferred_lft forever
2: eth0: <BROADCAST,MULTICAST,UP,LOWER_UP> mtu 1500 qdisc mq state UP group default qlen 1000
    link/ether dc:a6:32:d6:c4:f6 brd ff:ff:ff:ff:ff:ff
    inet 192.168.1.15/24 brd 192.168.1.255 scope global dynamic eth0
       valid_lft 86393sec preferred_lft 86393sec
    inet6 fe80::dea6:32ff:fed6:c4f6/64 scope link
       valid_lft forever preferred_lft forever
3: wlan0: <BROADCAST,MULTICAST,UP,LOWER_UP> mtu 1500 qdisc fq_codel state UP group default qlen 1000
    link/ether dc:a6:32:d6:c4:f7 brd ff:ff:ff:ff:ff:ff
    inet 192.168.1.4/24 brd 192.168.1.255 scope global dynamic wlan0
       valid_lft 84439sec preferred_lft 84439sec
4: wlan1: <NO-CARRIER,BROADCAST,MULTICAST,UP> mtu 1500 qdisc mq state DOWN group default qlen 1000
    link/ether 1c:bf:ce:55:e6:0b brd ff:ff:ff:ff:ff:ff

and I can see both in router

 

How Do I Set a Static IP Address on Raspberry Pi?

BYPHIL KING

UPDATED MAR 12, 2022

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Set a static IP

To set a static IP you need to replace the

dhcp4: true

line in the network-config file with lines that specify the intended IP address as well as its default gateway and DNS server. You can do this for either the eth0 or wlan0 interface (or both). It is important that you get the indenting right for this work correctly

For example, if you were planning to give the pi the address 192.168.1.17 in the 192.168.1.0/24 subnet with a default gateway of 192.168.1.1 and a DNS server of 192.168.1.53 then the following text would work. The same structure works for both the eth0 or wlan0 sections in the file:

ethernets:
  eth0:
    addresses:
      - 192.168.1.17/24
    gateway4: 192.168.1.1
    nameservers:
      addresses: [192.168.1.53]
    optional: true

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How to Set Static IP Address

The following is an example Netplan file with a network interface that has a static IP address. The interface’s name is en01 and it has been assigned static IP addresses 192.168.1.25/24 for IPv4, and 2001:1::1/64 for IPv6.

As both IPv4 and IPv6 have been assigned static IP addresses, each has a gateway set too.

DNS Name servers are also defined in this file. We’ll cover DNS a little further down in this tutorial.

network:
  version: 2
  renderer: networkd
  ethernets:
    en01:
      addresses:
      - 192.168.1.25/24
      - "2001:1::1/64"
      gateway4: 192.168.1.1
      gateway6: "2001:1::2"
      nameservers:
        addresses:
        - 8.8.8.8
        - 8.8.4.4

To apply changes to netplan you will need to reload your Netplan network configurations.

sudo netplan apply

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If you're using your Raspberry Pi as a media or game server, setting a static IP address will make things far easier.

If you’re using your Raspberry Pi as a home server or often need to access it remotely from another device, setting a static IP address for it is a very good idea. This means you’ll be able to find it at the same Raspberry Pi fixed IP address every time, rather than a new address being set dynamically whenever it is rebooted. This is also useful to avoid confusion when you have multiple Raspberry Pi devices connected to your network.

MAKEUSEOF VIDEO OF THE DAY

Fortunately, once you know how, it's a fairly simple and quick process to set a Raspberry Pi static IP address. We’ll show you how to change the IP address in Raspberry Pi OS to make it permanent.

What Is an IP Address?

An Internet Protocol (IP) address is used to uniquely identify each device on a computer network, or the network itself on the internet – more on that later. The IP address is normally written in ‘dot-decimal’ notation: four decimal numbers, each ranging from 0 to 255, separated by dots. An example is 192.168.1.107.

By default in Raspberry Pi OS, which is a Linux-based operating system, your Raspberry Pi’s IP address is reconfigured automatically each time you reboot it, so it may well change. Naturally, this is not ideal when you need a reliable address at which to connect to the Raspberry Pi from another device, such as when using it as a server. So it’s better to set a static IP address on Raspberry Pi.

Private vs. Public IP

A public IP address is used to identify your local network on the wider internet. This typically changes every time your router connects to the internet, although you may be able to make it static depending on your internet service provider.

You can find the public IP address on a Linux system such as Raspberry Pi OS by entering a special Terminal command, or simply by doing a web search for ‘What's my IP?’. It is only required if you intend to connect to a device from outside your network, which we won’t cover here.

Instead, we are looking at the private IP addresses used to identify each device on your own local network. While it may be possible to reserve a certain address for your Raspberry Pi in your wireless router’s settings for the same purpose, here we’ll be showing you how to set a static IP from the Raspberry Pi itself.

1. DHCP Configuration

Raspberry Pi OS (formerly know as Raspbian) uses DHCP (Dynamic Host Configuration Protocol) to assign an IP address to the Raspberry Pi automatically whenever it is rebooted. You can find out more in our guide to DHCP.

To change Raspberry Pi OS's behavior so that it uses the same static IP address each time, you will need to modify the configuration file for the DHCP client daemon, dhcpcd.conf.

Before that, you will need some information on your current network setup so you can add the required details to the configuration file. You will require the following info:

• The type of network connection. This is either wlan0 if your Raspberry Pi is connected to the router wirelessly, or eth0 if it’s connected using an Ethernet cable.

• The Raspberry Pi’s currently assigned IP address – it’s safest to reuse this for its static IP so that you can be sure the latter hasn’t already been to another device on the network. If not, make sure another device isn't already using it.

To find the Raspberry Pi’s current IP address, enter the following command in a Terminal window:

hostname -I

• Your router’s gateway IP address – the one used to contact it from the local network, not its public IP. It varies depending on the router model, but typically starts with 192.168.

To find it, enter the following command and note the first IP address given:

ip r | grep default

• Your router’s DNS (Domain Name System) IP address. This is typically the same as its gateway address, but may be set to another value to use an alternative DNS – such as 8.8.8.8 for Google, or 1.1.1.1 for Cloudflare.

To find the current DNS IP address, enter the command:

sudo nano /etc/resolv.conf

Note the IP address after nameserver – that's the DNS address – and then press Ctrl + X to close the file.

2. Add Static IP Settings

Now you have found all your network connection information, it’s time to edit the dhcpcd.conf configuration file to add the settings you need to set up a static IP address for your Raspberry Pi:

sudo nano /etc/dhcpcd.conf

If you haven’t edited the file previously, it will mainly contain various comment lines preceded by a hash (#) symbol. At the bottom, add the following lines, replacing the emboldened names with your own network details:

interface NETWORK 
static ip_address=STATIC_IP/24
static routers=ROUTER_IP 
static domain_name_servers=DNS_IP

Replace the emboldened names as follows:

• NETWORK – your network connection type: eth0 (Ethernet) or wlan0 (wireless).

• STATIC_IP – the static IP address you want to set for the Raspberry Pi.

• ROUTER_IP – the gateway IP address for your router on the local network.

• DNS_IP – the DNS IP address (typically the same as your router’s gateway address).

Here is an example configuration to set the static IP to 192.168.1.120 with a wireless connection to a router at 192.168.1.254:

interface wlan0
static ip_address=192.168.1.120/24
static routers=192.168.1.254
static domain_name_servers=192.168.1.254

Once you have entered the settings, press Ctrl + X and then Y and ENTER to close and save the modified configuration file.

3. Reboot the Raspberry Pi

With the dhcpcd.conf configuration file modified, restart your Raspberry Pi to effect the changes and set the static IP address for it:

sudo reboot

Rather than using an address assigned automatically by DHCP, the Raspberry Pi will now attempt to connect to the router using the new static IP address that you set in the dhcpcd.conf file.

To check that it is working correctly, enter the following command:

hostname -I

You should now see the static IP address that you set in the dhcpcd.conf configuration file.

Set a Static IP Address: Success

Congratulations: you have set up a static IP address on your Raspberry Pi, and it should now retain that address automatically whenever it boots up. Now you can go ahead and use your Pi system as a NAS, media or game server, and connect to it reliably at the same Raspberry Pi fixed IP address every time.

 

How to set WiFi Authentication

While WiFi is not something you would commonly configure Ubuntu server for, it it is prevalent enough you may consider using it in some use cases. To the following with walk you through configuring WPA and EAP wifi modes.

Systemd does not have native wifi support. In order for your network device to work with wifi you will need wpasupplicant installed.

Configuring WPA and EAP WiFi Connections

The most common home wifi configurations use mode WPA or EAP, while EAP is more common in enterprise. These two modes use a basic form of authentication using a password or shared-key.

For home users, the WPA mode is the simplest to use with a compatible wifi device. Devices that support WPA can automatically join wifi networks by pressing the WPA button on a compatible wifi router.

To configure WPA or EAP on Ubuntu using Netplan, you would add the auth scalar to your netplan configuration file. In the example below, we’ve added it to a ethernet interface named id0.

ethernets:
  id0:
    [...]
    access-points:
      mode: infrastructure
      bssid: mywifi
      band: 5GHz
      channel: 5
    auth:
      key-management: none | psk | eap 
      password: my-password-string

The access-points scalar sets how the wifi connection will be established.

• mode set the mode type for your wifi network interface. For connecting to access points the value should be set to infrastructure, which is the default.
• bassid is the name of your wifi connection, as configured on your access point.
• band is used to set the wireless band. It accepts two values: 5GHz and 2.4GHz. If left unset, the wifi endpoint and your network device will automatically establish the best band. By setting this value you will force the connection to use a specific band.
• channel is used to set your wifi channel, and only takes affect if the band property is set.

WPA and EAP connection modes accept the following configurations.

• key-management

  sets how the supported key management mode.

  • none to disable key management
  • psk for WPA with pre-shared key, common for home wifi.
  • eap for WPA with EAP, which is common for enterprise wifi networks.

• password sets the pre-shared key or password for your wifi network, when the mode is set to either psk or eap.

NetPlan Files

Network interfaces in Ubuntu 20.04 are configured in NetPlan YAML files, which are stored under /etc/netplan. The default file networking interfaces for a new Ubuntu 20.04 install is /etc/netplan/00-installer-config.yaml.

To edit the default netplan file, use the following command.

sudo vi /etc/netplan/00-installer-config.yaml

Alternatively, a simpler text editor by the name of nano can be used instead of vim.

sudo nano /etc/netplan/00-install-config.yaml

network:
    version: 2
    ethernets:
        eth0:
            dhcp4: true
            optional: true
    wifis:
        wlan0:
            access-points:
                "my_ssid":
                    password: "my_password"
            dhcp4: true
            optional: true

sudo netplan --debug apply
sudo systemctl enable wpa_supplicant
sudo systemctl start wpa_supplicant
sudo netplan generate
sudo netplan apply

sudo nano /etc/netplan/50-cloud-init.yaml

wifis:
  wlan0:
    dhcp4: true
    optional: true
    access-points:
      "home network":
        password: "123456789"