How to fix GKE network not ready: VPC/subnet configuration incomplete in Kubernetes

What this error means

This error occurs during cluster creation when Google Cloud cannot properly configure the virtual network for your cluster. GKE requires valid VPC, subnets with adequate IP space, firewall rules for inter-node communication, and proper routing tables. Without these, nodes cannot obtain IP addresses and pod networking fails to initialize.

Typical symptoms

• Cluster creation fails immediately with network error
• Nodes stuck in "NotReady" state indefinitely
• Network plugin (e.g., azure-cni) fails to initialize
• Pod CIDR allocation times out
• No node-to-node connectivity
• VPC subnet shows no available IPs
• GCP firewall blocks internal cluster traffic

Common causes

1. VPC subnet has insufficient IP address space (CIDR too small)
2. Secondary IP range not configured for pod CIDR
3. GCP firewall rules blocking traffic between nodes
4. Network route missing or misconfigured
5. Custom VPC without proper DNS or metadata server access
6. GKE VPC peering not established in Shared VPC setup
7. Network policy or Security group denying internal traffic

How to fix "GKE network not ready: VPC/subnet configuration incomplete"

Advanced notes

Related errors

• Failed to connect to server: connection refused (HTTP/2)

  How to fix "HTTP/2 connection refused" error in Kubernetes

  HIGH

• missing request for cpu in container

  How to fix "missing request for cpu in container" in Kubernetes HPA

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• error: invalid configuration

  How to fix "error: invalid configuration" in Kubernetes

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Official resources & further reading

• 📚Kubernetes Official Documentation
• 📖
  Kubernetes API Reference(Official Docs)
• 📖
  Kubernetes Tasks: Run Applications(Official Docs)
• 💬
  Stack Overflow: Kubernetes gke network not ready(Stack Overflow)
• 🐙
  Kubernetes GitHub Issues(GitHub)