---
title: How to create and manage routing policies
description: Find out how to create a routing policy for your Scaleway InterLink, allowing incoming and outgoing route announcements so that traffic can flow securely over your InterLink.
dates:
  validation: 2025-09-30
  posted: 2025-03-18
tags: interlink direct-connect allowed-routes route-propagation whitelist range IP announcements BGP
---
import scalewayCreateRoutingPolicy from './assets/scaleway-create-routing-policy.webp'


InterLink uses [**B**order **G**ateway **P**rotocol](/interlink/concepts/#border-gateway-protocol-bgp) to exchange routing information between the customer’s infrastructure and the Scaleway VPC. Each side advertises IP prefixes for its own internal subnets and resources, allowing the other side to dynamically learn and update its internal routes, facilitating efficient traffic flow. However, by default, **all routes across an InterLink are blocked**. You must create and attach [routing policies](/interlink/concepts/#routing-policy) to set IP prefix filters for the route advertisements you want to allow. This facilitates traffic flow across the InterLink.

An InterLink must have a **minimum of one** and a **maximum of two** attached routing policies, one for each IP traffic type to be routed (IPv4 and/or IPv6).

When creating a routing policy, you specify one or many IP ranges representing the outgoing routes to announce from the Scaleway VPC, and one or many IP ranges representing the incoming route announcements to accept from the external infrastructure. When [route propagation](/interlink/concepts/#route-propagation) is activated, the route ranges defined in the routing policy are allowed, and traffic can flow across the InterLink along these routes.

Learn more about routing across an InterLink in our [detailed overview](/interlink/reference-content/overview/#routing-across-an-interlink).

## How to create a routing policy

1. Click **InterLink** in the **Network** section of the [Scaleway console](https://console.scaleway.com) side menu. A listing of your InterLinks displays.

2. Click the **Routing policies** tab. A listing of your routing policies displays.

3. Click **+Create routing policy**. The **Create a routing policy** wizard displays.

        <Lightbox image={scalewayCreateRoutingPolicy} alt="In the Scaleway console, the create a routing policy wizard is displayed. There are 3 steps: 1. Choose a name and region, 2. allow outgoing routes, and 3. allow incoming routes" />

4. Choose a region for the policy. It can only be attached to InterLinks within the same region.

5. Define the type of IP traffic to be covered by the routing policy.

6. Allow the outgoing routes to allow. For each entry:
    - Enter an IP prefix to define a range of route announcements to allow, e.g., `172.16.4.0/22`.
    - Click **Add** when complete.

        <Message type="tip">
        Routes within these destinations will be propagated, allowing traffic from your external infrastructure to be routed via InterLink to your VPC. For example, adding `172.16.4.0/22` whitelists all 1,024 IPs in this block, from `172.16.4.0` to `172.16.7.255`.
        </Message>

7. Allow the incoming routes to allow, in the same way you did for outgoing routes. Outgoing routes concern announcements to accept from the external infrastructure. Traffic can be routed via InterLink from your Scaleway VPC to your external infrastructure along these routes.

8. Enter a name for the policy, or leave the randomly-generated name in place. Optionally, you can also add tags.

9. Click **Create routing policy**.

The policy is created, and you are returned to the listing of your routing policies.

Remember to [attach the policy to an InterLink](/interlink/how-to/configure-interlink/#how-to-attach-routing-policies) for it to take effect. Each InterLink can have only one routing policy for each IP traffic type attached to it, but a single routing policy can be attached to multiple InterLinks, if desired.

<Message type="tip">
See our dedicated documentation on using [BGP communities](/interlink/reference-content/bgp-communities/) to influence route priority for InterLink traffic.
</Message>

## How to edit an existing routing policy

1. Click **InterLink** in the **Network** section of the [Scaleway console](https://console.scaleway.com) side menu. A listing of your InterLinks displays.

2. Click on the **Routing Policy** tab. A list of your routing policies displays. Use the **region selector** at the top of the page to filter for the region of the routing policy you want to edit. 

3. Click <Icon name="more" /> next to the routing policy to edit, and select **Edit** in the menu that displays.

4. The **Edit routing policy** wizard displays. See the dedicated documentation on [creating and attaching a routing policy](/interlink/how-to/create-routing-policy/) for help with routing policies.

5. Make the required edits, and click **Edit routing policy**

        A warning displays, to remind you that modifications will immediately be propagated on InterLinks using this policy.

6. Click **Save**.

The policy is modified and modifications are immediately applied.