--- title: "Configuring an Additional IP block in a vRack" description: "As well as private IP addressing, the vRack also allows you to route public IP traffic through your server’s vRack port using a public IP address block." url: https://docs.us.ovhcloud.com/en/bare-metal-cloud/dedicated-servers/configuring-an-ip-block-in-a-vrack 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. # Configuring an Additional IP block in a vRack As well as private IP addressing, the [vRack](https://us.ovhcloud.com/network/vrack/) also allows you to route public IP traffic through your server’s vRack port using a public IP address block. **Warning:** **Limitations:** - IP blocks added to the vRack are limited to 5 Gbps. - This feature might be unavailable or limited on servers of the [Eco product line](https://eco.us.ovhcloud.com/about-us/). - Additional IP blocks purchased in the Singapore and Mumbai (YNM) data centers are not supported by vRack services. **Note:** vRack supports both IPv4 and IPv6 public routing with Additional IP address blocks. You can find the instructions on how to configure IPv6 blocks in our [Configuring an Additional IPv6 block in a vRack](https://docs.us.ovhcloud.com/en/bare-metal-cloud/dedicated-servers/configure-ipv6-in-vrack.md) guide. **Note:** This article focuses on Additional IP configuration over a vRack network. If you need guidance on Additional IP configuration with the primary IP (on the public network interface), read the following articles: - IPv4: - [Configuring IP aliasing on dedicated servers](https://docs.us.ovhcloud.com/en/bare-metal-cloud/dedicated-servers/configuring-ip-aliasing.md) - [Configuring IP aliasing on a VPS](https://docs.us.ovhcloud.com/en/bare-metal-cloud/vps/configuring-ip-aliasing.md) - IPv6: - [Configuring IPv6 on dedicated servers](https://docs.us.ovhcloud.com/en/bare-metal-cloud/dedicated-servers/network-ipv6.md) - [Configuring IPv6 on a VPS](https://docs.us.ovhcloud.com/en/bare-metal-cloud/vps/configuring-ipv6.md) - [Configuring IPv6 on a Public Cloud instance](https://docs.us.ovhcloud.com/en/public-cloud/network-services/ipv6-configuration.md)   ## Requirements - A public block of IP addresses in your account, with a minimum of four addresses - Your chosen private IP address range - A [vRack-compatible server](https://us.ovhcloud.com/bare-metal/) - An active [vRack](https://us.ovhcloud.com/network/vrack/) service in your account #### OVHcloud Control Panel Access - **Direct link:** [vRack](https://manager.us.ovhcloud.com/#/dedicated/vrack) - **Navigation path:** `Network` > `vRack private network`   ## Instructions **Note:** For example purposes, we'll be using an IP block of 46.105.135.96/28 and eth1 for the secondary network interface, which is dedicated to the vRack. Also, the network configuration file we refer to is located in `/etc/network/interfaces`. The equivalent file on your server may be located somewhere else, depending on your operating system. The file content may also be different. If you encounter any difficulties, please refer to the official documentation for your distribution. ### Add the IP block to the vRack **Warning:** **NOTE:** Once an IP block is added to the vRack, it is no longer attached to a physical server. This setup allows you to configure IPs of the same block on multiple servers, provided that these servers are all in the same vRack as the IP block. The IP block must have at least two usable IPs or more for this to be possible. Select your vRack from the list to display the list of eligible services. Choose the IP block you wish to add to the vRack and click on the `Add` button.   ### Configure a usable IP address **Warning:** **NOTE:** The IP blocks must be configured on the private interface. For vRack purposes, the first, penultimate, and last addresses in any given IP block are always reserved for the network address, network gateway, and network broadcast, respectively. This means that the first usable address is the second address in the block, as shown in the example below: ``` 46.105.135.96 Reserved: Network address 46.105.135.97 First usable IP 46.105.135.98 46.105.135.99 46.105.135.100 46.105.135.101 46.105.135.102 46.105.135.103 46.105.135.104 46.105.135.105 46.105.135.106 46.105.135.107 46.105.135.108 46.105.135.109 Last usable IP 46.105.135.110 Reserved: Network gateway 46.105.135.111 Reserved: Network broadcast ``` To configure the first usable IP address, we need to edit the network configuration file, as shown below. We will also need to use a subnet mask (**255.255.255.240**). **Note:** The subnet mask we've used in our example is appropriate for our IP block. Your subnet mask may differ depending on the size of your block. When you purchase your IP block, you’ll receive an email telling you which subnet mask to use.   ### Download the `iproute2` package Before you begin, download and install **iproute2**, a package for manual IP routing configuration. This package may already be available on your server — if so, skip to the next step. Establish an SSH connection to your server and run the following command from the command line. This will download and install iproute2. ``` sudo apt-get install iproute2 ``` **Fedora** ``` sudo dnf install iproute ```   ### Configure your VM #### Debian 11 **Configure the Additional IP** Using a text editor of your choice, open the network configuration file located in `/etc/network/interfaces.d` for editing. Here, the file is called `50-cloud-init`. ``` /etc/network/interfaces.d/50-cloud-init auto eth1 iface eth1 inet static address 46.105.135.97 netmask 255.255.255.240 broadcast 46.105.135.111 ```   **Create a new IP routing table** Next, we need to create a new IP route for the vRack. We'll be adding a new traffic rule by amending the file, as shown below: ``` sudo nano /etc/iproute2/rt_tables # # reserved values # 255 local 254 main 253 default 0 unspec # # local # #1 inr.ruhep 1 vrack ```   **Amend the network configuration file** For example purposes, the network configuration file we refer to is located in /etc/network/interfaces. The equivalent file on your server may be located somewhere else, depending on your operating system. Finally, we need to amend the network configuration file to account for the new traffic rule and route the vRack traffic through the network gateway address of **46.105.135.110**. ``` sudo nano /etc/network/interfaces.d/50-cloud-init auto eth1 iface eth1 inet static address 46.105.135.97 netmask 255.255.255.240 broadcast 46.105.135.111 post-up ip route add 46.105.135.96/28 dev eth1 table vrack post-up ip route add default via 46.105.135.110 dev eth1 table vrack post-up ip rule add from 46.105.135.96/28 table vrack post-up ip rule add to 46.105.135.96/28 table vrack ``` Now reboot your server to apply the changes, or enable the new network interface: ``` ip link set eth1 up ``` #### CentOS, AlmaLinux, and Rocky Linux (8/9) **Create the file for the secondary network interface** First, copy the primary network interface configuration and adjust it as needed: ``` sudo cp /etc/sysconfig/network-scripts/ifcfg-eth0 /etc/sysconfig/network-scripts/ifcfg-eth1 ``` Then, open the new file: ``` sudo nano /etc/sysconfig/network-scripts/ifcfg-eth1 ``` Define the IP settings: ``` # Created by cloud-init on instance boot automatically, do not edit. # DEVICE=eth1 BOOTPROTO=static ONBOOT=yes USERCTL=no IPV6INIT=no PEERDNS=yes TYPE=Ethernet NETMASK=255.255.255.240 IPADDR=46.105.135.97 ARP=yes ```   **Create a new IP routing table** Next, we need to create a new IP route for the vRack. We'll be adding a new traffic rule by amending the file, as shown below: ``` sudo nano /etc/iproute2/rt_tables # # reserved values # 255 local 254 main 253 default 0 unspec # # local # #1 inr.ruhep 1 vrack ``` Next, create the file needed to apply the new rules: ``` nano /etc/sysconfig/network-scripts/rule-eth1 ``` And paste the following content (please remember to replace our variables with your own values): ``` from 46.105.135.96/28 table vrack to 46.105.135.96/28 table vrack ```   **Amend the network configuration file** Finally, we need to amend the network configuration file to account for the new traffic rule and route the vRack traffic through the network gateway address of **46.105.135.110**. Edit the following file to add persistent and static routes: ``` nano /etc/sysconfig/network-scripts/route-eth1 ``` Paste the following content (please remember to replace our variables with your own values): ``` 46.105.135.96/28 dev eth1 table vrack default via 46.105.135.110 dev eth1 table vrack ``` Now reboot your server to apply the changes, or enable the new network interface: ``` ip link set eth1 up ``` #### Ubuntu & Debian 12+ Configure the Additional IP: Using a text editor of your choice, open the network configuration file located in `/etc/netplan` for editing. Here, the file is called `50-cloud-init.yaml`. ``` sudo nano /etc/netplan/50-cloud-init.yaml ``` Define the IP settings with the following variables: ``` NETWORK_INTERFACE: dhcp4: false addresses: - ADDITIONAL_IP/PREFIX routes: - to: NETWORK_IP/PREFIX via: GATEWAY_IP ``` **Example:** ``` eno2: dhcp4: false addresses: - 46.105.135.97/28 routes: - to: 46.105.135.96/28 via: 46.105.135.110 ``` Apply the configuration with the following command: ``` sudo netplan apply ``` #### Fedora, AlmaLinux, and Rocky Linux (10) First, verify that your vRack interface is `connected` or `connecting` state. In our example, the interface is called `eno2`. ``` nmcli device status DEVICE TYPE STATE CONNECTION eno1 ethernet connected cloud-init eno1 lo loopback connected (externally) lo eno2 ethernet connecting (getting IP configuration) vRack ``` Next, retrieve the name of the configuration file located in `/etc/NetworkManager/system-connections` for editing. Here the file is called `vRack.nmconnection`. ``` [user@server ~]$ cd /etc/NetworkManager/system-connections cloud-init-eno1.nmconnection vRack.nmconnection ``` Using the `nmcli` handler, configure your Additional IP. Replace `vRack` and other parameters with your own values. - Add the IP ``` sudo nmcli connection modify vRack IPv4.address 46.105.135.96/28 ``` - Add the Gateway ``` sudo nmcli connection modify vRack IPv4.gateway 46.105.135.110 ``` - Change the configuration from **auto** to **manual**: ``` sudo nmcli connection modify vRack IPv4.method manual ``` - Make the configuration persistent ``` sudo nmcli con mod 'vRack' connection.autoconnect true ```   **Create a new IP routing table** Next, we need to create a new IP route for the vRack. We'll be adding a new traffic rule (`1 vrack`) by amending the file, as shown below: ``` sudo nano /usr/share/iproute2/rt_tables # # reserved values # 255 local 254 main 253 default 0 unspec # # local # #1 inr.ruhep 1 vrack ``` Add the route: ``` sudo ip route add / via dev ``` **Example:** ``` sudo ip route add 46.105.135.96/28 via 46.105.135.110 dev eno2 ``` Restart your network with the following command: ``` sudo systemctl restart NetworkManager ``` #### Windows Server #### Step 1: Check and configure the secondary network interface First, check the new network interface information: Then, check the properties:   #### Step 2: IP Configuration Select the `Use the following IP address` option: Define the IP information:   #### Step 3: Rebooting the network interface First, disable the interface: Then, enable the interface:   ### Troubleshooting If you are unable to establish a connection from your VM or server to the private network, please send us a ticket from your control panel with the following: - IP source and IP destination - Ifconfig -a or ipconfig /all from both servers or VMs (setup network configuration interface) - ping in both ways - arp -a - Routing table Please, include the results from above in your ticket.   ## Go further Browse all the [Dedicated Servers guides](https://docs.us.ovhcloud.com/en/bare-metal-cloud/dedicated-servers/landing-page-dedicated-servers.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 [Dedicated Servers](https://us.ovhcloud.com/bare-metal/) on the OVHcloud US website.