--- title: "Configuring IPv6 on a VPS" description: "This article is about Primary IPv6 configuration on a public interface. You can also configure Additional IP addresses on your VPS using this guide." url: https://docs.us.ovhcloud.com/en/bare-metal-cloud/vps/configuring-ipv6 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 IPv6 on a VPS **Note:** This article is about Primary IPv6 configuration on a public interface. You can also configure Additional IP addresses on your VPS using [this guide](https://docs.us.ovhcloud.com/en/bare-metal-cloud/vps/configuring-ip-aliasing.md). **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/) in your OVHcloud account - Administrative access (root) via SSH or remote desktop (Windows) to your server - A basic understanding of networking - Access to the [OVHcloud Control Panel](https://manager.us.ovhcloud.com/) or [OVHcloud API](https://api.us.ovhcloud.com/)   ## Instructions The following sections contain configurations for the distributions we currently offer, as well as 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). **Warning:** **NOTE:** On the recent Linux operating systems we offer for VPS, the IPv6 address is configured by default. If this is the case, you don't need to configure it. Please check your operating system's configuration file before making any changes. Please take note of the following terminology that will be used in code examples and instructions of the guide sections below: | Term | Description | Example | | ------------- | --------------------------------------------------------- | --------------------------------------- | | YOUR\_IPV6 | The IPv6 address assigned to your service | 2001:xxxx:xxxx:xxxx:xxxx:xxxx:xxxx:yyyy | | IPv6\_PREFIX | The prefix (or _netmask_) of your IPv6 block, usually 128 | 2001:xxxx:xxxx:xxxx::/128 | | IPv6\_GATEWAY | The gateway of your IPv6 block | 2001:xxxx:xxxx:xxxx:xxxx:xxxx:xxxx:zzzz |   ### Step 1: Retrieve the necessary network information The first step is to identify the IPv6 address and the IPv6 gateway assigned to your server. There are two ways of doing this: #### Via OVHcloud Control Panel Log into the [OVHcloud Control Panel](https://manager.us.ovhcloud.com/) and navigate to your VPS via the `Bare Metal Cloud` and `Virtual private servers` menus. The IPv6 address and the IPv6 gateway assigned to your server will appear in the **IP** panel of the `Home` tab. Once you have copied them, continue with [applying the IPv6 configuration](#step-2-apply-the-ipv6-configuration). #### Via OVHcloud API From the [OVHcloud API](https://api.us.ovhcloud.com/), click on `Login` in the top-right corner. On the following page, enter the credentials of your OVHcloud account. Use this call to retrieve the IPv6 address assigned to your server: [GET /vps/{serviceName}/ips](https://api.us.ovhcloud.com/console/?section=/vps&branch=v1#get-/vps/-serviceName-/ips) The following call allows you to recover the IPv6 gateway assigned to your server: [GET /vps/{serviceName}/ips/{ipAddress}](https://api.us.ovhcloud.com/console/?section=/vps&branch=v1#get-/vps/-serviceName-/ips/-ipAddress-) Once you have retrieved these addresses, continue with [applying the IPv6 configuration](#step-2-apply-the-ipv6-configuration).   ### Step 2: Apply the IPv6 configuration Once you have gathered the necessary information for the IPv6 configuration, log in to your VPS via SSH. If you require assistance, please refer to this guide: [How to get started with SSH connections](https://docs.us.ovhcloud.com/en/bare-metal-cloud/dedicated-servers/ssh-introduction.md). There are several ways to apply the IPv6 configuration. Use whichever method best suits your situation and requirements: - Non-persistent application - Persistent application on Debian and its derivatives - Persistent application on Red Hat and its derivatives - Persistent application on Fedora 42 and later - Persistent application on Windows Server **Warning:** **NOTE:** VPS LE instances have two interfaces by default. The IPv6 configuration might need to be applied to a different interface, e.g., `eth1`. You can confirm which interface is used with the command: `ip addr`. If this is the case for you, the command may look like this: ``` ip addr add YOUR_IPV6/IPV6_PREFIX dev eth1 ip -6 route add IPV6_GATEWAY dev eth1 ip -6 route add default via IPV6_GATEWAY dev eth1 ``` #### Non-persistent #### Non-persistent application **Warning:** **NOTE:** This configuration will be lost after a restart of your VPS (non-persistent configuration). Connect to your server via SSH and enter the following commands. Take care to tailor these with: - the network information, retrieved in the previous step (_YOUR\_IPV6_, _IPV6\_PREFIX_, and _IPV6\_GATEWAY_) - the network interface (if your server is not using **eth0**) ``` ip addr add YOUR_IPV6/IPV6_PREFIX dev eth0 ip -6 route add IPV6_GATEWAY dev eth0 ip -6 route add default via IPV6_GATEWAY dev eth0 ``` ##### Persistent(Debian, etc.) #### Persistent application on Debian and its derivatives (Ubuntu, Crunchbang, etc.) **Warning:** **NOTE:** Before modifying a configuration file, always create a backup of the original. There are two ways to configure your network, depending on the operating system installed on your server: - **For Debian 11:** use the method based on the _interfaces_ files - **For Debian 12, Ubuntu 22.04 and later:** use the method based on the _Netplan_ configuration In some cases, the appropriate method may not be the one specified above. To make sure, browse your system to check which one is active. Visit [https://netplan.io/](https://netplan.io/) for more information, if necessary. Moreover, keep in mind that the exact file names may vary.   **Configuration of _****interfaces****_ files** By default, the configuration files are located in `/etc/network/interfaces.d/`.  The best practice is to create a separate configuration file in the `/etc/network/interfaces.d/` directory to configure the IPv6 address. In our example, the file is called `51-cloud-init-ipv6`. ``` sudo nano /etc/network/interfaces.d/51-cloud-init-ipv6 ``` This allows you to separate the IPv6 configuration and easily revert the changes in case of an error. Add the following lines to the file. Replace the generic elements (i.e. _YOUR\_IPV6_, _IPV6\_PREFIX_ and _IPV6\_GATEWAY_) as well as the network interface (if your server is not using **eth0**) with your specific values. ``` auto eth0 iface eth0 inet6 static mtu 1500 address YOUR_IPV6 netmask IPV6_PREFIX post-up /sbin/ip -6 route add IPV6_GATEWAY dev eth0 post-up /sbin/ip -6 route add default via IPV6_GATEWAY dev eth0 pre-down /sbin/ip -6 route del default via IPV6_GATEWAY dev eth0 pre-down /sbin/ip -6 route del IPV6_GATEWAY dev eth0 ``` ##### Configuration example: ``` auto eth0 iface eth0 inet6 static mtu 1500 address 2607:5300:201:abcd::7c5 netmask 128 post-up /sbin/ip -6 route add 2607:5300:201:abcd::1 dev eth0 post-up /sbin/ip -6 route add default via 2607:5300:201:abcd::1 dev eth0 pre-down /sbin/ip -6 route del default via 2607:5300:201:abcd::1 dev eth0 pre-down /sbin/ip -6 route del 2607:5300:201:abcd::1 dev eth0 ``` Then, restart your network service with one of the following commands: ``` sudo service networking restart ``` ``` sudo systemctl restart networking ``` Alternatively, you can add the configuration above to one of the following files (with _sudo_ privileges), depending on the generation of the operating system installed on the server: - the `/etc/network/interfaces` file - the `/etc/network/interfaces.d/50-cloud-init.cfg` file We recommend that you back up the relevant configuration file. For example, use the following command: ``` sudo cp /etc/network/interfaces /etc/network/interfaces.bak ``` You will then be able to revert the changes, using the commands below: ``` sudo rm -f /etc/network/interfaces sudo cp /etc/network/interfaces.back /etc/network/interfaces ```   **Configuration using Netplan** The network configuration files are located in the `/etc/netplan/` directory. By default, the main configuration file is called `50-cloud-init.yaml`. Before continuing, first check this file to see if the IPv6 address has already been configured. If so, you don't need to configure the IPv6 address again, as you only have one IPv6 address with your VPS server. If the IPv6 address has not been configured, the best approach is to create a separate configuration file to set up the IPv6 address in the `/etc/netplan/` directory. This way, you can easily revert the changes in case of an error. In addition, we recommend that you adjust the permissions for the newly created file. For more information about file permissions, consult the [official documentation of Ubuntu](https://help.ubuntu.com/community/FilePermissions). In our example, our file is named `51-cloud-init-ipv6.yaml`: ``` sudo nano /etc/netplan/51-cloud-init-ipv6.yaml ``` Then edit the `51-cloud-init-ipv6.yaml` file, adding the IPv6 configuration of your server. Replace the generic elements (i.e. _YOUR\_IPV6_, _IPV6\_PREFIX_ and _IPV6\_GATEWAY_) as well as the network interface (if your server is not using **eth0**) with your specific values. ``` network: version: 2 ethernets: eth0: dhcp6: false match: name: eth0 addresses: - YOUR_IPV6/IPv6_PREFIX routes: # If IPV6_PREFIX is 128 then add link route to gateway # - to: IPv6_GATEWAY # scope: link - to: ::/0 via: IPv6_GATEWAY ``` ##### Configuration example (with prefix /128): ``` network: version: 2 ethernets: eth0: dhcp6: false match: name: eth0 addresses: - 2607:5300:201:abcd::7c5/128 routes: - to: 2607:5300:201:abcd::1 scope: link - to: ::/0 via: 2607:5300:201:abcd::1 ``` **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. Only the space key is needed. You can test your configuration using this command: ``` sudo netplan try ``` If it is correct, apply it using the following command: ``` sudo netplan apply ``` ###### Persistent(Red Hat, etc.) #### Persistent application on Red Hat and its derivatives (CentOS, Rocky Linux, Alma Linux, etc.) The network configuration files are located in the `/etc/sysconfig/network-scripts/` directory. We recommend that you start by backing up the relevant configuration file. For example, copy the `ifcfg-eth0` file using the following commands. Remember to replace **eth0** with your actual interface if necessary. ``` cd /etc/sysconfig/network-scripts/ sudo mkdir backup sudo cp ifcfg-eth0 backup/ifcfg-eth0 ``` You will then be able to revert the changes, using the commands below: ``` sudo rm -f /etc/sysconfig/network-scripts/ifcfg-eth0 sudo cp /etc/sysconfig/network-scripts/backup/ifcfg-eth0 /etc/sysconfig/network-scripts/ifcfg-eth0 ``` Then edit the `ifcfg-eth0` file, adding the IPv6 configuration of your server. Replace the generic elements (i.e. _YOUR\_IPV6_, _IPV6\_PREFIX_ and _IPV6\_GATEWAY_) with your specific values. Also, we have omitted the IPv4 configuration to avoid confusion, but the IPv6 configuration is made in the same configuration file. ``` IPV6INIT=yes IPV6ADDR=YOUR_IPV6/IPV6_PREFIX IPV6_DEFAULTGW=IPV6_GATEWAY ``` ##### Configuration example: ``` IPV6INIT=yes IPV6ADDR=2607:5300:201:abcd::7c5/128 IPV6_DEFAULTGW=2607:5300:201:abcd::1 ``` **On CentOS 7, you have to create a routing file in addition to the steps above:** - Create a file (with _sudo_ privileges), indicating the default IPv6 routes: ``` sudo touch /etc/sysconfig/network-scripts/route6-eth0 ``` - Edit the file and add the lines below. Replace the generic elements (_IPV6\_GATEWAY_ and **eth0** interface, if necessary) with your specific values. ``` IPV6_GATEWAY dev eth0 default via IPV6_GATEWAY ``` ##### Example: ``` 2607:5300:201:abcd::1 dev eth0 default via 2607:5300:201:abcd::1 ``` Finally, restart your network service to allow the system to apply the new configuration with one of the following commands: ``` sudo service networking restart ``` ``` sudo systemctl restart networking ``` ###### Persistent(Fedora 42+) #### Persistent application on Fedora 42 and later The network configuration file is located in the `/etc/NetworkManager/system-connections/`. We recommend that you start by backing up the relevant configuration file. In our example, our file is called `cloud-init-eth0.nmconnection`, so we copy the `cloud-init-eth0.nmconnection` file using the following commands. Remember to replace **eth0** with your actual interface if necessary. ``` cd /etc/NetworkManager/system-connections/ sudo mkdir backup sudo cp cloud-init-eth0.nmconnection backup/cloud-init-eth0.nmconnection ``` Then we edit the `cloud-init-eth0.nmconnection` file, adding only the lines for the IPv6 configuration of the server. Replace the generic elements (i.e. _YOUR\_IPV6_, _IPV6\_PREFIX_, and _IPV6\_GATEWAY_) with your specific values. If we assume that your interface is eth0, the configuration should look like this: ``` [ipv6] method=auto may-fail=true address1=YOUR_IPV6/IPV6_PREFIX route1=::/0,IPV6_GATEWAY ``` We have omitted the IPv4 configuration to avoid confusion, but the IPv6 configuration is made in the same configuration file. ##### Example: ``` [ipv6] method=auto may-fail=true address1=2607:5300:201:abcd::7c5/128 route1=::/0,2607:5300:201:abcd::1 ``` ###### Persistent(Windows) #### Persistent application on Windows Server By default, IPv6 is not configured on Windows Servers. To enable it, open the `Control Panel` and click on `View network status and tasks`, then on `Change adapter settings`. Click on `Ethernet` to open the settings and click on the `Properties` button to view the `Ethernet Properties`. Select `Internet Protocol Version 6 (TCP/IPv6)`, then click on the `Properties` button. In the IPv6 Properties window, select `Use the following IPv6 address`. Enter the IP addresses that you have retrieved in the first step. You also have the option of entering the IPv6 DNS resolvers of your choice under `Use the following DNS server addresses`. This is not mandatory if the DNS resolvers of the IPv4 configuration are already functional. Finally, tick the `Validate settings upon exit` box and click the `OK` button to validate your changes. An error message may appear if the specified gateway is not on the same IPv6 subnet (/128 and /64 for example). You can ignore this message and continue to the next step regardless.   ### Step 3: Verify the configuration and test the connection To verify that the configuration is functional, there are several possible commands, depending on the operating system. - **For a GNU/Linux-based system**, here are two examples for the **eth0** interface (to be adapted if necessary): ``` ip -6 addr show eth0 2: eth0: mtu 1500 qlen 1000 inet6 2001:xxxx:xxxx:xxxx:xxxx:xxxx:zzzz/128 scope global valid_lft forever preferred_lft forever inet6 fe80::f816:3eff:fec0:c336/64 scope link valid_lft forever preferred_lft forever ``` ``` ifconfig eth0 eth0 Link encap:Ethernet HWaddr ab:cd:ef:gf:ij:kl inet addr:aa.bb.cc.dd Bcast:aa.bb.cc.ee Mask:255.255.255.255 inet6 addr: 2001:xxxx:xxxx:xxxx:xxxx:xxxx:zzzz/128 Scope:Global inet6 addr: fe80::f816:3eff:fec0:c336/64 Scope:Link UP BROADCAST RUNNING MULTICAST MTU:1500 Metric:1 [...] ``` To test the connection, you can use the following command: ``` ping6 proof.ovh.us ``` - **For a Windows-based system**, use the following command: ``` ipconfig Windows IP Configuration Ethernet adapter Ethernet: Connection-specific DNS Suffix . : openstacklocal IPv6 Address. . . . . . . . . . . : 2001:xxxx:xxxx:xxxx::zzzz Link-local IPv6 Address . . . . . : fe80::d928:7a00:5ba6:951b%3 IPv4 Address. . . . . . . . . . . : 51.xxx.xxx.xxx Subnet Mask . . . . . . . . . . . : 255.255.255.255 Default Gateway . . . . . . . . . : 2001:xxxx:xxxx:xxxx::y 51.xxx.xxx.y ``` To test the connection, you can use the following command: ``` ping -6 proof.ovh.us ``` You can also test the connection to another remote server. However, it is necessary for IPv6 to be active on the remote server for this operation to work. **Note:** If, despite these changes, IPv6 does not seem to work on your server, it is possible (in rare cases) that you will have to carry out additional modifications. In such cases, try the following steps: - Depending on the operating system, try to change the prefix (or _netmask_) of your IP address from /128 to /64. This will include the IPv6 gateway in your subnet. - In addition to restarting the network service, it may be necessary to reboot your server to finalize your IPv6 configuration. - In Windows, verify that the firewall allows ICMP requests for IPv6.   ### Step 4: Disable Cloud-init network management (optional) **Note:** This step does not apply to Windows-based systems. Cloud-init is a package installed by default on a VPS. It functions as a framework to run a script after initially creating your server or rebooting it. The mechanics in place allow the underlying OpenStack infrastructure to inject scripts into the Cloud-init environment and, therefore, the server configuration. Depending on the operating system, Cloud-init will manage: the network, the hostname, the resolv.conf file, or the automatic partitioning of the hard disk, in case of an upgrade. In the case of newer distributions (such as CentOS, Debian 9, Ubuntu 16.x, and later), the default configuration of Cloud-init might sometimes automatically reset the network configuration when the server starts up. This is relevant for specific use cases in which it is recommended to avoid the reset by disabling automatic network management in Cloud-init. To do this, use the following command to create a file `/etc/cloud/cloud.cfg.d/98-disable-network-config.cfg` with the value `network: {config: disabled}`: ``` sudo echo "network: {config: disabled}" > /etc/cloud/cloud.cfg.d/98-disable-network-config.cfg ``` **Warning:** **NOTE:** It might be necessary to reboot the server for the change to take effect. To return to automatic management of your network by Cloud-init, delete the newly created file or move it to another directory.   ## 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.