--- title: "Configure IP autodetection" description: "Pick how Calico Enterprise detects each node's primary IP — first-found, Kubernetes internal, interface regex, CIDR, or skip-interface — for reliable routing." product: "Calico Enterprise" version: "3.23 (latest)" section: "Networking" canonical_url: "https://docs.tigera.io/calico-enterprise/latest/networking/ipam/ip-autodetection" --- # Configure IP autodetection ## Big picture Configure IP autodetection for Calico Enterprise nodes to ensure the correct IP address is used for routing. ## Value When you install Calico Enterprise on a node, an IP address and subnet is automatically detected. Calico Enterprise provides several ways to configure IP/subnet autodetection, and supports configuring specific IPs for: - Hosts with multiple external interfaces - Host interfaces with multiple IP addresses - [Changes to cross subnet packet encapsulation](https://docs.tigera.io/calico-enterprise/latest/networking/configuring/vxlan-ipip.md) - Changes to host IP address ## Concepts ### Autodetecting node IP address and subnet For internode routing, each Calico Enterprise node must be configured with an IPv4 address and/or an IPv6 address. When you install Calico Enterprise on a node, a node resource is automatically created using routing information that is detected from the host. For some deployments, you may want to update autodetection to ensure nodes get the correct IP address. **Sample default node resource after installation** ```yaml apiVersion: projectcalico.org/v3 kind: Node metadata: name: node-hostname spec: bgp: asNumber: 64512 ipv4Address: 10.244.0.1/24 ipv6Address: 2000:db8:85a3::8a2e:370:7335/120 ipv4IPIPTunnelAddr: 192.168.0.1 ``` ### Autodetection methods By default, Calico Enterprise uses the **firstFound** method; the first valid IP address on the first interface (excluding local interfaces such as the docker bridge). However, you can change the default method to any of the following: - Address used by the node to reach a particular IP or domain (**canReach**) - Address assigned to Kubernetes node (**kubernetes: InternalIP**) - Regex to include matching interfaces (**interface**) - Regex to exclude matching interfaces (**skipInterface**) - A list of IP ranges in CIDR format to determine valid IP addresses on the node to choose from (**cidrs**) For help on autodetection methods, see [NodeAddressAutodetection](https://docs.tigera.io/calico-enterprise/latest/reference/installation/api.md#nodeaddressautodetection) in the operator Installation reference and for more details see the [node configuration](https://docs.tigera.io/calico-enterprise/latest/reference/component-resources/node/configuration.md#ip-autodetection-methods) reference. ### Manually configure IP address and subnet To manually configure an IP address and subnet, disable autodetection and update the node resources with the IP address. ## How to - [Change the autodetection method](#change-the-autodetection-method) - [Manually configure IP address and subnet for a node](#manually-configure-ip-address-and-subnet-for-a-node) ### Change the autodetection method As noted previously, the default autodetection method is **first valid interface found** (firstFound). To use a different autodetection method, configure the NodeAddressAutodetection field(s) in the Installation resource. You can update the Installation resource before applying it during installation or edit it later with `kubectl edit installation default`. > **SECONDARY:** To configure the default autodetection method for IPv6 for any of the below methods, use the field `nodeAddressAutodetectionV6`. - **Kubernetes Node IP** Calico Enterprise will select the first internal IP address listed in the Kubernetes node's `Status.Addresses` field. ```yaml kind: Installation apiVersion: operator.tigera.io/v1 metadata: name: default spec: calicoNetwork: nodeAddressAutodetectionV4: kubernetes: NodeInternalIP ``` - **Source address used to reach an IP or domain name** Calico Enterprise will choose the IP address that is used to reach the given "can reach" IP address or domain. For example: ```yaml kind: Installation apiVersion: operator.tigera.io/v1 metadata: name: default spec: calicoNetwork: nodeAddressAutodetectionV4: canReach: 8.8.8.8 ``` - **Including matching interfaces** Calico Enterprise will choose an address on each node from an interface that matches the given [regex](https://pkg.go.dev/regexp). For example: ```yaml kind: Installation apiVersion: operator.tigera.io/v1 metadata: name: default spec: calicoNetwork: nodeAddressAutodetectionV4: interface: eth.* ``` - **Excluding matching interfaces** Calico Enterprise will choose an address on each node from an interface that does not match the given [regex](https://pkg.go.dev/regexp). For example: ```yaml kind: Installation apiVersion: operator.tigera.io/v1 metadata: name: default spec: calicoNetwork: nodeAddressAutodetectionV4: skipInterface: eth.* ``` - **Including CIDRs** Calico Enterprise will select any IP address from the node that falls within the given CIDRs. For example: ```yaml kind: Installation apiVersion: operator.tigera.io/v1 metadata: name: default spec: calicoNetwork: nodeAddressAutodetectionV4: cidrs: - '192.168.200.0/24' ``` - **IPv4** ```yaml apiVersion: operator.tigera.io/v1 kind: Installation metadata: name: default spec: variant: CalicoEnterprise ... calicoNetwork: nodeAddressAutodetectionV4: : ``` - **IPv6** ```yaml apiVersion: operator.tigera.io/v1 kind: Installation metadata: name: default spec: variant: CalicoEnterprise ... calicoNetwork: nodeAddressAutodetectionV6: : ``` > **SECONDARY:** You can use both `nodeAddressAutodetectionV4` and `nodeAddressAutodetectionV6` to specify IPv4 and IPv6 methods. ### Manually configure IP address and subnet for a node In the following scenarios, you may want to configure a specific IP and subnet: - Hosts with multiple external interfaces - Host interfaces with multiple IP addresses - Changes to cross subnet packet encapsulation - Changes to host IP address You can configure specific IP address and subnet for a node by disabling IP autodetection and then updating the [Node resource](https://docs.tigera.io/calico-enterprise/latest/reference/resources/node.md). #### Disable autodetection To disable autodetection method, update the proper `NodeAddressAutodetection` field in the Installation resource: ```yaml apiVersion: operator.tigera.io/v1 kind: Installation metadata: name: default spec: variant: CalicoEnterprise ... calicoNetwork: nodeAddressAutodetectionV4: {} nodeAddressAutodetectionV6: {} ``` #### Configure IP and subnet using node resource You can also configure the IP address and subnet on a Node resource. > **SECONDARY:** When configuring the IP address on a Node resource, you may want to disable IP address options or environment variables on the node. IP options on the container take precedence, and will overwrite the values you configure on the node resource. Use `calicoctl patch` to update the current node configuration. For example: ```text calicoctl patch node kind-control-plane \ --patch='{"spec":{"bgp": {"ipv4Address": "10.0.2.10/24", "ipv6Address": "fd80:24e2:f998:72d6::/120"}}}' ``` ## Additional resources - For details on autodetection methods, see the [node configuration](https://docs.tigera.io/calico-enterprise/latest/reference/component-resources/node/configuration.md) reference. - For calicoctl environment variables, see [Configuring node](https://docs.tigera.io/calico-enterprise/latest/reference/component-resources/node/configuration.md) - [Node resource](https://docs.tigera.io/calico-enterprise/latest/reference/resources/node.md) - [Reference documentation for calicoctl patch](https://docs.tigera.io/calico-enterprise/latest/reference/clis/calicoctl/patch.md)