How to configure the network of a virtual machine on a Dedibox host

Reviewed on January 30, 2025

When you install your server with a virtualization solution like Proxmox, you can create multiple virtual machines on the physical server. This setup allows you to have separate environments for different services (e.g., mail and web services) or to optimize the server's performance by running several virtual machines.

To communicate on the internet, each of your virtual machines needs an IP address. You can use failover IPs to have additional IP addresses available for your server.

Tip

You can configure a unique gateway for your virtual machines, allowing them to move between hypervisors without changing their network configuration.

IP address of the unique gateway: 62.210.0.1

Before you start

To complete the actions presented below, you must have:

A Dedibox account logged into the console
Created a Dedibox dedicated server and installed a hypervisor on it
Ordered a failover IP
Generated a virtual MAC address

Find below examples of network interface configurations on different distributions inside a virtual machine:

Ubuntu

Since the release of version 18.04 (Bionic Beaver), Ubuntu has used Netplan for configuring network interfaces. For older releases, refer to the Debian configuration.

Log into your virtual machine and open the network configuration file /etc/netplan/01-netcfg.yaml in a text editor of your choice:
```
sudo nano /etc/netplan/01-netcfg.yaml
```

Create a network configuration as follows. Replace <failover_IP> with your failover IP address:

network:
  version: 2
  ethernets:
    ens18:
      addresses:
        - <failover_IP>/32
      nameservers:
        addresses: [ "51.159.47.28", "51.159.47.26" ]
      routes:
        - to: default
          via: 62.210.0.1
        - to: 62.210.0.1/32
          via: <failover_IP>
          scope: link

Save the file and exit the text editor.
Apply the new configuration:
```
sudo netplan apply
```

Debian

Log into the virtual machine and edit the network configuration file:
```
sudo nano /etc/network/interfaces
```

Configure the network interface as follows. Replace <failover_IP> with your failover IP address:

auto eth0
iface eth0 inet static
    address <failover_IP>
    netmask 255.255.255.255
    pointopoint 62.210.0.1
    gateway 62.210.0.1

Save the file and exit the text editor.
Set the DNS server information:
```
sudo nano /etc/resolv.conf
```

Add the following DNS resolvers:

nameserver 51.159.47.28
nameserver 51.159.47.26

Activate the network on your virtual machine:
```
sudo ifup eth0
```
Alternatively, you can restart networking with:
```
sudo systemctl restart networking
```

CentOS

Log into the virtual machine and edit the network configuration file:
```
sudo nano /etc/sysconfig/network-scripts/ifcfg-eth0
```

Configure the network interface as follows. Replace <failover_IP> with your failover IP address and <virtual_MAC> with the virtual MAC of the VM:

DEVICE=eth0
BOOTPROTO=none
ONBOOT=yes
USERCTL=no
IPV6INIT=no
PEERDNS=yes
TYPE=Ethernet
NETMASK=255.255.255.255
IPADDR=<failover_IP>
GATEWAY=62.210.0.1
DNS1=51.159.47.28
DNS2=51.159.47.26
ARP=yes
HWADDR=<virtual_MAC>

Save and close the text editor.

Create or edit the routing configuration file:

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

Add the following lines:

62.210.0.1 dev eth0
default via 62.210.0.1 dev eth0

Activate the network interface:
```
sudo ifup eth0
```

Windows Server

Open the network settings on your VM by navigating to:

Control Panel → Network & Internet → Change Adapter Options

Select your network adapter and enter the following details:
- IP Address: <failover_IP>
- Subnet Mask: 255.255.255.255
- Gateway: 62.210.0.1
- DNS 1: 51.159.47.28
- DNS 2: 51.159.47.26

Tip

Replace the IP of the DNS cache server with the one located in the same physical location as your machine for optimal performance. Check the IPs for each data center