Configure IPv4 IPs & Subnets

If you’ve purchased any additional IPv4 addresses for your service, Fixed or Failover. These will need to be configured inside your server. We only configure the main server IPv4 on our side.

The correct method for adding extra IPs or subnets depends on the operating system you’re using, as each distribution handles network configuration differently.

Red Hat Enterprise Linux (RHEL / AlmaLinux / RockyLinux)

Do not use eth0-x files to configure additional IPs or Subnets in your server. No support is provided for servers using eth0-x files.

On the First2Host network, your primary network interface is usually eth0, as shown below.

Copy the UUID of the interface, then run the command below, replacing the example UUID with your own.

nmcli connection edit 5fb06bd0-0bb0-7ffb-45f1-d6edd65f3e03

You can view the currently assigned IPv4 addresses using the print command. In most cases, you’ll only see your virtual server’s main IPv4 address.

print ipv4.address

To configure additional IPv4 or IPv6 addresses, you can use the set ipv4.address and set ipv6.address commands.

set ipv4.address

In the console, specify all of the IPv4 addresses you want to configure on the server. Make sure each IPv4 address is separated by a comma.

51.xXx.149.x, 91.xXx.173.172, 137.xx.49.2X2, 198.xXx.4.8

Once you’ve added all of your IPv4 or IPv6 addresses, run save and then quit. After that, reboot the server to ensure the configuration is fully applied.

Ubuntu / Debian

In Ubuntu and Debian servers, you use Netplan to configure any additional IPs and subnets. It’s very important to maintain the correct indentation in the file — if the spacing is incorrect, your network configuration will fail.

For that reason, always run netplan try before applying the changes. This allows you to confirm the configuration is valid and automatically rolls back if something is wrong.

The Netplan configuration file is located at/etc/netplan/50-cloud-init.yaml. Its default form is below. 

network:
  version: 2
  ethernets:
    eth0:
      match:
        macaddress: "bc:24:11:42:df:88"
      addresses:
      - "5.175.67.192/27"
      - "2001:41d0:203:5ca7::14/117"
      nameservers:
        addresses:
        - 213.186.33.99
        - 8.8.8.8
        - 2001:4860:4860::8888
        search:
        - f2hdns.com
      set-name: "eth0"
      routes:
      - on-link: true
        to: "default"
        via: "51.198.88.215"
      - to: "default"
        via: "2001:41d0:209:5ca7::2"

To configure further IPv4 on your server. Just add further IPs to the addresses section.

network:
  version: 2
  ethernets:
    eth0:
      match:
        macaddress: "bc:24:11:42:df:88"
      addresses:
      - "5.175.67.192/27"
      - "149.209.35.24/32"
      - "5.135.4.231/32"
      - "2001:41d0:203:5ca7::14/117"
      nameservers:
        addresses:
        - 213.186.33.99
        - 8.8.8.8
        - 2001:4860:4860::8888
        search:
        - f2hdns.com
      set-name: "eth0"
      routes:
      - on-link: true
        to: "default"
        via: "51.198.88.215"
      - to: "default"
        via: "2001:41d0:209:5ca7::2"

Once finished, issue netplan try and netplan apply to apply the network configuration to your servers.