Alias IP Ranges

Configure secondary IP ranges for instances via the aliasIPRanges field in GCPMachineTemplate.

This enables CNI plugins like Cilium to use Native Routing by allocating pod and service IPs from the alias ranges.

---
apiVersion: infrastructure.cluster.x-k8s.io/v1beta1
kind: GCPMachineTemplate
metadata:
  name: mygcpmachinetemplate
  namespace: mynamespace
spec:
  template:
    spec:
      image: projects/myproject/global/images/myimage
      instanceType: n1-standard-2
      aliasIPRanges:
      - ipCidrRange: /24
        subnetworkRangeName: pods
      - ipCidrRange: 10.96.0.0/16
        subnetworkRangeName: services

The ipCidrRange accepts:

• CIDR notation: 10.0.0.0/24
• IP address only: 10.0.0.1
• Netmask only: /24

The subnetworkRangeName is optional and references a secondary IP range configured on the subnet.

https://cloud.google.com/vpc/docs/alias-ip