Your organization is running out of private IPv4 IP addresses.

The most effective long-term solution to address IPv4 address exhaustion in GKE clusters, while still ensuring routability and unique ranges per cluster, is to transition to dual-stack IPv4/IPv6 clusters and leverage IPv6 for Pods and Services. This allows you to conserve IPv4 addresses for critical use cases while providing a vast address space with IPv6 for pods and services, significantly reducing the pressure on your private IPv4 ranges. Google Cloud GKE fully supports dual-stack networking.

Exact Extract:

"Dual-stack clusters enable you to assign both IPv4 and IPv6 addresses to Pods and Services. This approach helps conserve IPv4 address space by shifting a significant portion of the network communication to IPv6, particularly for internal cluster communication or communication with other IPv6-enabled services."

"When you enable dual-stack networking, GKE assigns an IPv6 address range to your Pods and can also assign IPv6 addresses to Services. This significantly expands the available addressing capacity within your cluster."Reference: Google Kubernetes Engine Documentation - Dual-stack networking