# Configure IPv6 Addresses

As we described, for managed Elastic IPv6 prefix a single reference IPv6 address will be transparently forwarded to
the attached instances without any configuration needed. For all the other cases, manual configuration is needed within the Compute instances.

Some common use cases are:

- To employ a managed Elastic IPv6 prefix, and you need to use more IPv6 addresses than the reference address.
- To employ a manual Elastic IPv6 prefix.

> [!WARNING]
> **Do not remove the original IPv6 address** of the compute instance, as Elastic IPv6 relies on it.

Configuration of additional IPv6 addresses within your compute instance may vary depending the operating system.
Some examples follow:

### Ubuntu 
Ubuntu 22.04.5 LTS (Jammy Jellyfish)

In `/etc/netplan/51-eip.yaml`, put the following snippet.

```yaml
---
network:
  version: 2
  renderer: networkd
  ethernets:
    lo:
      match:
        name: lo
      addresses:
        - 2a04:c45:c00:3a46:500:2::1337/128
```

And then, apply it with `sudo netplan apply`

### Debian
Debian 11 (Bullseye)

In `/etc/network/interfaces.d/51-eipv6` add the following snippet:

```bash
    auto lo:1
    iface lo:1 inet6 static
        address 2a04:c44:c00:3a46:500:2::1337/128
```

Then invoke `ifup lo:1` to configure the IPv6 address on respective interface.
For additional IPv6 addresses from the Elastic IPv6 prefix, use `lo:2`, `lo:3`, et cetera.