---
title: "Early Network Configuration"
description: "Reference for the EarlyNetworkConfiguration resource in Calico Enterprise that brings up BGP networking before the kubelet starts."
product: "Calico Enterprise"
version: "3.23 (latest)"
section: "Reference"
canonical_url: "https://docs.tigera.io/calico-enterprise/latest/reference/resources/earlynetworkconfiguration"
---

# Early Network Configuration

Early network configuration supplies labels and AS numbers to apply to each Calico Enterprise node, as well as peering and other network configuration to use during node startup prior to receiving BGPPeer and BGPConfiguration resources from the datastore. Early network configuration will be superseded by any BGPPeer or BGPConfiguration resources after successful startup.

Early network configurations are intended for use only when Calico Enterprise is being run in "early networking" mode, i.e. when operating a "dual ToR" networking configuration. If you are not running a dual-plane cluster, this is probably not what you are looking for! For configuring BGP networking under normal circumstances (when Calico Enterprise is running), see [BGPConfiguration](https://docs.tigera.io/calico-enterprise/latest/reference/resources/bgpconfig.md), [BGPPeer](https://docs.tigera.io/calico-enterprise/latest/reference/resources/bgppeer.md), and [BGPFilter](https://docs.tigera.io/calico-enterprise/latest/reference/resources/bgpfilter.md).

For a detailed guide on how to set up dual ToR, see [Deploy a dual ToR cluster](https://docs.tigera.io/calico-enterprise/latest/networking/configuring/dual-tor.md).

## Sample YAML

EarlyNetworkConfiguration differs from other Calico Enterprise resources, in that it is not directly applied with `kubectl` / `calicoctl`.

Instead, an EarlyNetworkConfiguration should be wrapped in a config-map named "bgp-layout" and placed in the "tigera-operator" namespace. It should also be copied to the filesystem of each node, so that Calico Enterprise, running in early networking mode, may read it, prior to any Kubernetes services being available.

```yaml
apiVersion: projectcalico.org/v3
kind: EarlyNetworkConfiguration
spec:
  platform: openshift
  nodes:
      # worker1
    - interfaceAddresses:
        - 172.31.11.3
        - 172.31.12.3
      stableAddress:
        address: 172.31.10.3
      asNumber: 65001
      peerings:
        - peerIP: 172.31.11.100
        - peerIP: 172.31.12.100
      labels:
        rack: ra
      # worker2
    - interfaceAddresses:
        - 172.31.21.4
        - 172.31.22.4
      stableAddress:
        address: 172.31.20.4
      asNumber: 65002
      peerings:
        - peerIP: 172.31.21.100
        - peerIP: 172.31.22.100
      labels:
        rack: rb
  legacy:
    nodeIPFromDefaultRoute: false
    unconditionalDefaultRouteProgramming: false
```

## Sample ConfigMap

```yaml
apiVersion: v1
kind: ConfigMap
metadata:
  name: bgp-layout
  namespace: tigera-operator
data:
  earlyNetworkConfiguration: |
  apiVersion: projectcalico.org/v3
  kind: EarlyNetworkConfiguration
  spec:
    nodes:
    # worker1
    - interfaceAddresses:
    ...
```

## Early Network Configuration Definition

### Spec

| Field    | Description                                                                                                                  | Accepted Values                      | Schema Default |
| -------- | ---------------------------------------------------------------------------------------------------------------------------- | ------------------------------------ | -------------- |
| platform | The platform the cluster runs on. Unless running on OpenShift, can be left empty.                                            | "", "openshift"                      | ""             |
| nodes    | List of [ConfigNode](#confignode) objects; provides the information necessary for each node to bootstrap dual ToR networking | [ConfigNode](#confignode) list       | Empty          |
| legacy   | [LegacyConfig](#legacyconfig) object, for toggling legacy behavior                                                           | [LegacyConfig](#legacyconfig) object | Empty          |

### ConfigNode

| Field              | Description                                                                                                                                                                                 | Accepted Values                                    | Schema Default |
| ------------------ | ------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------- | -------------------------------------------------- | -------------- |
| interfaceAddresses | List of IP addresses assigned to interfaces on this node                                                                                                                                    | list of IP addresses                               | Empty          |
| asNumber           | The AS number of this node's BIRD.                                                                                                                                                          | integer                                            | 0              |
| stableAddress      | The [ConfigStableAddress](#configstableaddress) that Calico Enterprise should assign to this node, describing the IP address that normal traffic should use for communicating with the node | [ConfigStableAddress](#configstableaddress) object | Empty          |
| peerings           | List of [ConfigPeering](#configpeering) objects. Provides information about a node's ToRs, so that Calico Enterprise early-networking can establish a BGP session with them                 | [ConfigPeering](#configpeering) list               | Empty          |
| labels             | Any labels that the node should have, so as to match the right BGPPeer definitions for its rack, when node runs as a Kubernetes pod.                                                        | labels map                                         | Empty          |

### LegacyConfig

| Field                                | Description                                                                                                                                                                   | Accepted Values | Schema Default |
| ------------------------------------ | ----------------------------------------------------------------------------------------------------------------------------------------------------------------------------- | --------------- | -------------- |
| nodeIPFromDefaultRoute               | Toggles legacy behavior, where Calico Enterprise early networking would use the src IP of a default route to identify which ConfigNode to use.                                | true, false     | false          |
| unconditionalDefaultRouteProgramming | Toggles legacy behavior, where Calico Enterprise early networking would unconditionally program a default route to a ToR, regardless of whether one existed prior to startup. | true, false     | false          |

### ConfigStableAddress

| Field   | Description                                                                                         | Accepted Values   | Schema Default |
| ------- | --------------------------------------------------------------------------------------------------- | ----------------- | -------------- |
| address | IP address which Calico Enterprise should provision during early networking as the "stable" address | IP Address string | ""             |

### ConfigPeering

| Field        | Description                                                                                                    | Accepted Values   | Schema Default |
| ------------ | -------------------------------------------------------------------------------------------------------------- | ----------------- | -------------- |
| peerIP       | The IP address of the ToR                                                                                      | IP Address string | ""             |
| peerASNumber | The AS number of the ToR. When left as 0, Calico Enterprise early networking will use its own node's AS number | integer           | 0              |