Flexible IP configuration for VMs on Bare Metal Cloud servers

Virtualization - Overview

Virtualization technologies allow to create multiple virtual machines on one physical host. This allows better usage of the available computing power and associated resources like storage and RAM.

It is possible to create virtual machines (VM) on Bare Metal Cloud Servers using available solutions, like VMware ESXi, XEN or KVM.

The management of these virtual interfaces is possible either via the command line from a command-line-interface, or by using web based administration panels. These can either come directly built-in within the virtualization solution like it is the case for ESXi or they can be third-party software built around an existing solution like Proxmox, an interface for KVM based virtual machines or LXC paravirtualized containers.

The network connectivity of these virtual machines can be assured by assigning them a flexible IP with a virtual MAC address. While the virtual MAC address can be configured using the management tool of your hypervisor, the flexible IP has to be configured directly from the guest OS of the virtual machine.

Below you find configuration instructions for virtual machines running on:


  • You have an account and are logged into console.scaleway.com
  • You have a Bare Metal Cloud Server running a hypervisor.
  • You have a Bare Metal flexible IP with an assigned virtual MAC address.
  • You have sudo privileges or access to the root user.

Note: The unique Gateway for all Bare Metal flexible IPs is: The DNS resolvers provided by Scaleway are and

Note: This documentation concerns Flexible IPs for Bare Metal Cloud Servers. Flexible IPs for Virtual Instances have different functionalities and are not managed in the same way: please see the relevant documentation.

Network Configuration on a Ubuntu VM

On Ubuntu Bionic Beaver (18.04 LTS) or later, you can use Netplan to configure the networking of the virtual machine. If you prefer a more traditonal configuration, refer to the Debian section.

1 . Open the Netplan configuration file /etc/netplan/01-netcfg.yaml in a text editor of your choice, for example nano:

nano /etc/netplan/01-netcfg.yaml

The IP address must be written in CIDR notation inside the configuration file. The netmask for all flexible IPs is /32.

2 . To make the virtual machine reachable over the Internet, the route information must be specified in the configuration file. Once edited, your configuration file looks like the following example. Remember to replace fail.over.ip.address with your flexible IP address:

  version: 2
  renderer: networkd
      dhcp4: no
      dhcp6: no
      addresses: [fail.over.ip.address/32]
        addresses: [,]
      - to:
        via: fail.over.ip.address
        scope: link

3 . Activate the new configuration by running the following command:

netplan apply

Network Configuration on a Debian VM

1 . Open the file /etc/network/interfaces in your favourite text editor, i.e nano:

nano /etc/network/interfaces

2 . Edit the network configuration as shown in the following example. Do not forget to replace fail.over.ip.address with your flexible IP.

auto eth0
iface eth0 inet static
    address fail.over.ip.address

3 . Save the filex, exit the text editor. Then open the file /etc/resolv.conf in the text editor:

nano /etc/resolv.conf

4 . Enter the information about the DNS resolver. You can either use Scaleway’s DNS resolvers or any other you want to use:


5 . Save the file and activate the new configuration by activating the network interface:

ifup eth0

Network Configuration on a CentOS VM

1 . Open the file /etc/sysconfig/network-scripts/ifcfg-eth0 in a text editor, for example nano:

nano /etc/sysconfig/network-scripts/ifcfg-eth0

2 . Edit the file as shown below. Do not forget to replace fail.over.ip.address with your flexible IP and virtual:mac:address with the virtual MAC addressociated to the IP.


3 . Save the file and exit the text editor.

4 . Open the file /etc/sysconfig/network-scripts/route-eth0 in a text editor, for example nano:

nano /etc/sysconfig/network-scripts/route-eth0

5 . Edit the file as shown below to configure the default route of the virtual machine: dev eth0
default via dev eth0

6 . Activate the new configuration by enabling the network interface of the virtual machine:

ifup eth0

Network Configuration on a CentOS VM

1 . Connect to the desktop of your virtual machine using the console interface of your hypervisor.

2 . Open the Network configuration in the Windows Control Panel.

3 . Double click on the network adapter of your virtual machine and enter the following information. Replace fail.over.ip.address with your flexible IP address:

Address: fail.over.ip.address
DNS 1:
DNS 2:

Discover the Cloud That Makes Sense