How to configure a Dedibox failover IP on Debian and Ubuntu
This guide provides step-by-step instructions for configuring a Dedibox failover IP on Debian and Ubuntu Linux. A failover IP is a secondary IP address that can be assigned to your server.
Before you start
To complete the actions presented below, you must have:
Failover IP configuration on Debian
-
Connect to your server using SSH and open the network configuration file
/etc/network/interfaces
in a text editor, such asnano
:nano /etc/network/interfaces
-
Add the failover IP to the configuration as shown in the following example:
# This file describes the network interfaces available on your system # and how to activate them. For more information, see interfaces(5). # The loopback network interface auto lo iface lo inet loopback # The primary network interface auto eth0 iface eth0 inet static address 195.154.123.123 netmask 255.255.255.0 gateway 195.154.123.1 auto eth0:0 iface eth0:0 inet static address ip_failover netmask 255.255.255.255
-
Save the file and exit the editor. Bring up the interface using the following command:
ifup eth0:0
Failover IP configuration on Ubuntu (Netplan)
Since Ubuntu 18.04, Netplan has been the default network configuration system.
-
Disable cloud-init network configuration to prevent conflicts with Netplan:
sudo mkdir -p /etc/cloud/cloud.cfg.d echo 'network: {config: disabled}' | sudo tee /etc/cloud/cloud.cfg.d/99-disable-network-config.cfg
-
Backup the existing Netplan configuration and create a new file:
sudo cp /etc/netplan/50-cloud-init.yaml /etc/netplan/01-myplan.yaml sudo mv /etc/netplan/50-cloud-init.yaml /etc/netplan/50-cloud-init.yaml-backup
-
Edit the new Netplan configuration file
/etc/netplan/01-myplan.yaml
usingnano
:network: renderer: networkd ethernets: enp5s0: critical: true dhcp-identifier: mac dhcp4: false dhcp6: false addresses: - 51.111.222.333/24 # Server main IP (/24) - 212.111.222.333/32 # Alternate IPs / IP redirects (/32) - 212.111.222.334/32 - 212.111.222.335/32 routes: - to: 0.0.0.0/0 via: 62.210.0.1 metric: 1 on-link: true nameservers: addresses: - 51.159.69.156 - 51.159.69.162 enp6s0: dhcp4: true dhcp4-overrides: use-routes: false routes: - to: 10.88.0.0/13 # Use appropriate IP/gateway from DHCP via: 10.89.23.129 version: 2
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Run the following command to test the configuration:
sudo netplan try
-
If everything works as expected, apply the configuration:
sudo netplan apply
Troubleshooting
If you encounter issues with your network configuration, check the logs using:
sudo journalctl -u systemd-networkd --no-pager
You can also refer to the official Canonical repository for more Netplan examples and troubleshooting guides.