--- title: "How to configure IP aliasing" description: "IP aliasing is a special network configuration for your OVHcloud servers that allows you to associate multiple IP addresses with a single network interface." url: https://docs.us.ovhcloud.com/en/bare-metal-cloud/vps/configuring-ip-aliasing lang: en --- > For AI agents: the complete documentation index is available at https://docs.us.ovhcloud.com/en/llms.txt, the full documentation bundle is available at https://docs.us.ovhcloud.com/en/llms-full.txt. # How to configure IP aliasing IP aliasing is a special network configuration for your OVHcloud servers that allows you to associate multiple IP addresses with a single network interface. **Warning:** **NOTE:** OVHcloud provides services for which you are responsible for their configuration and management. You are therefore responsible for their proper functioning.\ \ This tutorial is designed to help you as much as possible with common tasks. If you are having difficulty performing these actions, please contact a specialized service provider. OVHcloud cannot provide you with technical support in this regard.   ## Requirements - A [Virtual Private Server](https://us.ovhcloud.com/vps/) on your OVHcloud account - An [Additional IP](https://us.ovhcloud.com/network/additional-ip/) address or an Additional IP block - Administrative access (sudo) via SSH or GUI to your server - Basic networking and administration knowledge **Warning:** **NOTE:** Additional IP addresses are currently unavailable for Virtual Private Servers in [Local Zones](https://us.ovhcloud.com/vps/vps-amd/).   ## Instructions The following sections contain the configurations for the most commonly used distributions/operating systems. The first step is always to log in to your server via SSH or a GUI login session (RDP for a Windows VPS). The examples below presume you are logged in as a user with elevated permissions (Administrator/sudo). **Note:** Concerning different distribution releases, please note that the proper procedure to configure your network interface, as well as the file names, may have been subject to change. We recommend consulting the manuals and knowledge resources of the respective OS versions, if you experience any issues. **Please take note of the following terminology that will be used in code examples and instructions of the guide sections below:** | | | | | ------------------ | -------------------------------------------------------------------------------------------------------- | -------------- | | **Term** | **Description** | **Examples** | | ADDITIONAL\_IP | An Additional IP address assigned to your service | 203.0.113.0 | | NETWORK\_INTERFACE | The name of the network interface | _eth0_, _ens3_ | | ID | ID of the IP alias, starting with _0_ (depending on the number of additional IPs there are to configure) | _0_, _1_ |   Select the tab below that corresponds to your operating system: ### Debian 11 ### Debian 11 #### Step 1: Disable automatic network configuration Open the following file path with a text editor. In our example, we are using `nano`: ``` sudo nano /etc/cloud/cloud.cfg.d/99-disable-network-config.cfg ``` Enter the following line, then save and exit the editor: ``` network: {config:disabled} ``` Creating this configuration file will prevent changes to your network configuration from being made automatically.   #### Step 2: Create a backup By default, the configuration file is located in the path `etc\network\interfaces.d`. In our example, our file is called `50-cloud-init`, so we make a copy of the `50-cloud-init` file using the following command: ``` sudo cp /etc/network/interfaces.d/50-cloud-init /etc/network/interfaces.d/50-cloud-init.bak ``` In case of a mistake, you will be able to revert the changes using the commands below: ``` sudo rm -f /etc/network/interfaces.d/50-cloud-init sudo cp /etc/network/interfaces.d/50-cloud-init.bak /etc/network/interfaces.d/50-cloud-init ```   #### Step 3: Edit the network configuration file You can verify your network interface name with this command: ``` ip a ``` Open the network configuration file for editing with the following command: ``` sudo nano /etc/network/interfaces.d/50-cloud-init ``` To configure your Additional IP, you need to add a virtual interface or ethernet alias to your network interface. In our example, our interface is called `eth0`, so our first alias is `eth0:0`. Do this for each Additional IP you wish to configure. Do not modify the existing lines in the configuration file; simply add your Additional IP to the file as follows, replacing `NETWORK_INTERFACE`, `ID`, and `ADDITIONAL_IP` with your own values: ``` auto NETWORK_INTERFACE:ID iface NETWORK_INTERFACE:ID inet static address ADDITIONAL_IP netmask 255.255.255.255 ``` If you are configuring more than one Additional IP, your configuration file should look like this: ``` auto NETWORK_INTERFACE:ID iface NETWORK_INTERFACE:ID inet static address ADDITIONAL_IP1 address ADDITIONAL_IP2 netmask 255.255.255.255 ``` ##### Configuration example: ``` auto eth0:0 iface eth0:0 inet static address 203.0.113.0 netmask 255.255.255.255 ```   #### Step 4: Restart the interface Apply the changes with the following command: ``` sudo systemctl restart networking ``` ##### Debian 12+, Ubuntu 22.04+ ### Debian 12+, Ubuntu 22.04+ The configuration file for your Additional IP addresses is located in the folder `/etc/netplan/`. In this example, it is called `50-cloud-init.yaml`. The best practice approach is to create a separate configuration file to set up Additional IP addresses. This way, you can easily revert the changes in case of an error. #### Step 1: Create the network configuration file In our example, our file is called `51-cloud-init.yaml`: ``` sudo touch /etc/netplan/51-cloud-init.yaml ```   #### Step 2: Edit the configuration file You can verify your network interface name with this command: ``` ip a ``` Next, open the network configuration file for editing with the following command: ``` sudo nano /etc/netplan/50-cloud-init.yaml ``` Edit the file with the content below, replacing `INTERFACE_NAME` and `ADDITIONAL_IP` with your own values: ``` network: version: 2 ethernets: INTERFACE_NAME: dhcp4: true addresses: - ADDITIONAL_IP/32 ``` If you have more Additional IPs to configure, the configuration file should look like this: ``` network: version: 2 ethernets: INTERFACE_NAME: dhcp4: true addresses: - ADDITIONAL_IP1/32 - ADDITIONAL_IP2/32 ``` **Warning:** **NOTE:** It is important to respect the alignment of each element in this file as represented in the example above. Do not use the tab key to create your spacing. ##### Configuration example: ``` network: version: 2 ethernets: eth0: dhcp4: true addresses: - 203.0.113.0/32 ``` Save and close the file.   #### Step 3: Apply the new network configuration You can test your configuration using this command: ``` sudo netplan try ``` If it is correct, apply it using the following command: ``` sudo netplan apply ``` ##### AlmaLinux / Rocky Linux ### AlmaLinux 8/9/10, Rocky Linux 8/9/10 The main configuration file is located in `/etc/sysconfig/network-scripts/`. In this example, it is called `ifcfg-eth0`. Before making changes, verify the actual file name in this folder. For each Additional IP to be configured, we create a separate configuration file with the following parameters: `ifcfg-NETWORK_INTERFACE:ID`. Where `NETWORK_INTERFACE` is the physical interface and `ID` is the virtual network interface or ethernet alias starting with a value of 0. For example, for our interface named `eth0` the first alias is `eth0:0`, the second alias is `eth0:1`, etc...   #### Step 1: Determine the interface ``` ip a ```   #### Step 2: Create the configuration file First, create the configuration file. Replace `NETWORK_INTERFACE:ID` with your own values. ``` sudo nano /etc/sysconfig/network-scripts/ifcfg-NETWORK_INTERFACE:ID ``` Next, edit the file with the content below, replacing `NETWORK_INTERFACE:ID`, and `ADDITIONAL_IP` with your own values: ``` DEVICE=NETWORK_INTERFACE:ID ONBOOT=yes BOOTPROTO=none # For CentOS use "static" IPADDR=ADDITIONAL_IP NETMASK=255.255.255.255 BROADCAST=ADDITIONAL_IP ``` ##### Configuration example: ``` DEVICE=eth0:0 ONBOOT=yes BOOTPROTO=none # For CentOS use "static" IPADDR=203.0.113.0 NETMASK=255.255.255.255 BROADCAST=203.0.113.0 ```   #### Step 3: Restart the interface ``` sudo systemctl restart NetworkManager ```   **For CentOS** ``` sudo systemctl restart network ``` ##### Fedora 42 ### Fedora 42 Fedora now uses keyfiles. NetworkManager previously stored network profiles in ifcfg format in this directory: `/etc/sysconfig/network-scripts/`. However, the ifcfg format is now deprecated. By default, NetworkManager no longer creates new profiles in this format. The configuration file is now found in `/etc/NetworkManager/system-connections/`.   #### Step 1: Create a backup In our example, our file is called `cloud-init-eno1.nmconnection`, so we make a copy of the `cloud-init-eno1.nmconnection` file using the following command: ``` sudo cp -r /etc/NetworkManager/system-connections/cloud-init-eno1.nmconnection /etc/NetworkManager/system-connections/cloud-init-eno1.nmconnection.bak ``` In case of a mistake, you will be able to revert the changes using the commands below: ``` sudo rm -f /etc/NetworkManager/system-connections/cloud-init-eno1.nmconnection sudo cp /etc/NetworkManager/system-connections/cloud-init-eno1.nmconnection.bak /etc/NetworkManager/system-connections/cloud-init-eno1.nmconnection ```   #### Step 2: Edit the config file **Note:** Please note that the name of the network file in our example may differ from yours. Please adapt the commands to your file name. ``` sudo nano /etc/NetworkManager/system-connections/cloud-init-eno1.nmconnection ``` Do not modify the existing lines in the configuration file; add your Additional IP to the file as follows, replacing `ADDITIONAL_IP/32` wih your own values: ``` [ipv4] method=auto may-fail=false address1=ADDITIONAL_IP/32 ``` If you have two Additional IPs to configure, the configuration should look like this: ``` [ipv4] method=auto may-fail=false address1=ADDITIONAL_IP1/32 address2=ADDITIONAL_IP2/32 ``` ##### Configuration example: ``` [ipv4] method=auto may-fail=false address1=203.0.113.0/32 ```   #### Step 3: Restart the interface You now need to restart your interface: ``` sudo systemctl restart NetworkManager ``` ##### cPanel ### cPanel #### Step 1: Access the WHM IP management section In the WHM control panel, click on `IP Functions` and select `Add a New IP Address` in the left-hand sidebar.   #### Step 2: Add the Additional IP information Enter your Additional IP in the form `xxx.xxx.xxx.xxx` into the field “New IP or IP range to add”. Select `255.255.255.255` as your subnet mask, then click on `Submit`. **Warning:** **NOTE:** Please note that if you have more than one IP to configure on the same block and you add them all at once, the WHM system will force you to use the subnet mask `255.255.255.0`. We do not recommend using this configuration. Instead, you need to add each IP individually to use the proper subnet mask `255.255.255.255`.   #### Step 3: Check the current IP configuration Back in the section `IP Functions`, click on `Show or Delete Current IP Addresses` to verify that the Additional IP address was added correctly. ##### Plesk ### Plesk #### Step 1: Access the Plesk IP management section In the Plesk control panel, choose `Tools & Settings` from the left-hand sidebar. Click on `IP Addresses` under **Tools & Resources**.   #### Step 2: Add the additional IP information In this section, click on the button `Add IP Address`. Enter your Additional IP in the form `xxx.xxx.xxx.xxx/32` into the field "IP address and subnet mask", then click on `OK`.   #### Step 3: Check the current IP configuration Back in the section "IP Addresses", verify that the Additional IP address was added correctly. ##### Windows Servers ### Windows Servers #### Step 1: Verify the network configuration Right-click on the `Start Menu` button and open `Run`. Type `cmd` and click `OK` to open the command line application. To retrieve the current IP configuration, enter `ipconfig` at the command prompt. ``` C:\Users\Administrator>ipconfig Windows IP Configuration Ethernet adapter Ethernet: Connection-specific DNS Suffix . : openstacklocal Link-local IPv6 Address . . . . . : fe90::30gf:258a:84d6:abcf%5 IPv4 Address. . . . . . . . . . . : 192.0.2.29 Subnet Mask . . . . . . . . . . . : 255.255.255.255 Default Gateway . . . . . . . . . : 192.0.2.1 ```   #### Step 2: Change the IPv4 Properties Now you need to change the IP properties to a static configuration. 1. Go to `Start`> `Control Panel`>`Network and Internet`> `Network and Sharing Center`> `Change Adapter Settings`(in the left-hand menu). 2. Right-click on `Ethernet`. 3. Click on `Properties`. 4. Select `Internet Protocol Version 4 (TCP/IPv4)`, then click on `Properties`. 5. Click on `Use the following IP address` and type in your server’s primary IP, subnet mask, and default gateway information obtained by using the `ipconfig` command above. In the "Preferred DNS Server" box, type `213.186.33.99`. Be careful – the server will no longer be accessible if you enter incorrect information. You will then have to make the corrections in the KVM. Once done, click on `Advanced`.   #### Step 3: Add the Additional IP in the "Advanced TCP/IP Settings" In the new window, click on `Add...` under "IP addresses". Enter your Additional IP address and the subnet mask (255.255.255.255). Confirm by clicking on `Add`. Once done, click on `OK` to apply the configuration. You will lose the connection to the server for a few seconds.   #### Step 4: Check the new network configuration Open the command prompt (cmd) and enter `ipconfig`. The configuration should now include the new Additional IP address. ``` C:\Users\Administrator>ipconfig Windows IP Configuration Ethernet adapter Ethernet: Connection-specific DNS Suffix . : Link-local IPv6 Address . . . . . : fe90::30gf:258a:84d6:abcf%5 IPv4 Address. . . . . . . . . . . : 192.0.2.29 Subnet Mask . . . . . . . . . . . : 255.255.255.255 IPv4 Address. . . . . . . . . . . : 203.0.113.0 Subnet Mask . . . . . . . . . . . : 255.255.255.255 Default Gateway . . . . . . . . . : 192.0.2.1 ```   ### Troubleshooting First, restart your server from the command line or its GUI. If you are still unable to establish a connection from the public network to your alias IP and suspect a network problem, you need to reboot the server in [rescue mode](https://docs.us.ovhcloud.com/en/bare-metal-cloud/vps/recover-rescue-mode.md). Then you can set up the Additional IP address directly on the server. Once you are connected to your server via SSH, enter the following command: ``` ifconfig ens3:0 ADDITIONAL_IP netmask 255.255.255.255 broadcast ADDITIONAL_IP up ``` To test the connection, simply ping your Additional IP from the outside. If it responds in rescue mode, which probably means that there is a configuration error. If, however, the IP is still not working, please inform our support teams by [creating a support request](https://docs.us.ovhcloud.com/en/account/account-information/contact-us-support.md) for further investigations.   ## Go further Browse all the [Virtual Private Servers guides](https://docs.us.ovhcloud.com/en/bare-metal-cloud/vps/landing-page-vps.md). Browse the rest of the [OVHcloud US documentation](https://docs.us.ovhcloud.com/en/index.md) for guides on our other products and services. Learn more about [VPS](https://us.ovhcloud.com/vps/) on the OVHcloud US website.