> ## Documentation Index
> Fetch the complete documentation index at: https://docs.gcore.com/llms.txt
> Use this file to discover all available pages before exploring further.

# Configure an additional IP address

> Configure an additional IP address in the operating system after purchase, including network interface settings and verification.

Purchasing an additional IP address assigns it to the server, but it must still be configured in the operating system before it becomes usable.

**1. In the Gcore Hosting control panel, open the Virtual private servers or Dedicated servers tab**

**2. Select the checkbox next to the server**

**3. View the IP addresses and note the netmask**

Click **IP addresses** in the toolbar. Note the IP address and its netmask — these are required for the configuration.

![Virtual private servers list with the IP addresses button highlighted in the toolbar](https://mintcdn.com/gcore/494jjlOXZiI1ohtY/images/docs/hosting/virtual-servers/manage/networking/additional-ip-addresses/configure-an-additional-ip-address/configure-an-additional-ip-address-image1.png?fit=max\&auto=format\&n=494jjlOXZiI1ohtY\&q=85\&s=68848603ec8066072a081163cefb01ed)

![Dedicated servers list with the IP addresses button highlighted in the toolbar](https://mintcdn.com/gcore/494jjlOXZiI1ohtY/images/docs/hosting/virtual-servers/manage/networking/additional-ip-addresses/configure-an-additional-ip-address/configure-an-additional-ip-address-image2.png?fit=max\&auto=format\&n=494jjlOXZiI1ohtY\&q=85\&s=a3068e6b28db3b2ed5e1a1e404f77cd8)

**4. Configure the IP address in the OS**

Select the operating system and follow the steps.

**Debian and Ubuntu**

Edit the network interfaces file to add the IP address.

1. Open `/etc/network/interfaces`.
2. Add the configuration.

For IPv4:

```sh theme={null}
auto eth0:N
iface eth0:N inet static
    address X.X.X.X
    netmask 255.255.255.255
```

For IPv6 (optional):

```sh theme={null}
iface eth0:N inet6 static
    address 2001:X:X:X::X
```

Replace `N` with the sequential index of the additional IP address (starting at `0` for the first), `X.X.X.X` with the IP address, and `255.255.255.255` with the actual netmask.

3. Save the file.
4. Restart networking: run `systemctl restart networking`.

After restarting, run `ip addr show` to verify the new address appears on the interface.

**CentOS**

Create a per-interface configuration file for each additional IP address.

1. Create the file `/etc/sysconfig/network-scripts/ifcfg-eth0:N`.
2. Add the configuration.

For IPv4:

```sh theme={null}
DEVICE=eth0:N
ONBOOT=yes
BOOTPROTO=static
IPADDR=X.X.X.X
NETMASK=255.255.255.255
```

For IPv6 (optional):

```sh theme={null}
IPV6ADDR_SECONDARIES="2001:X:X:X::X/64"
```

Replace `N` with the sequential index of the additional IP address (starting at `0` for the first), `X.X.X.X` with the IP address, and `255.255.255.255` with the actual netmask.

3. Save the file.
4. Restart networking: run `systemctl restart network`.

After restarting, run `ip addr show` to verify the new address appears on the interface.