Google Distributed Cloud Edge Pod and Service network address allocation

This page describes best practices for allocating network addresses to Kubernetes Pods and Services running on your Google Distributed Cloud Edge installation.

The following address ranges are reserved and must not overlap Distributed Cloud Edge Pod or Distributed Cloud Edge Service address blocks:

  • 10.128.0.0/20
  • 10.138.0.0/20

When creating a Distributed Cloud Edge Cluster, you can specify an IPv4 CIDR block for your Distributed Cloud Edge Pods and Distributed Cloud Edge Services. For IPv4, use the RFC 1918 address range. each Distributed Cloud Edge Cluster accepts a single contiguous Distributed Cloud Edge Pod CIDR block and a single contiguous Distributed Cloud Edge Service CIDR block. The Distributed Cloud Edge Service CIDR block covers only ClusterIP Services running within the target Distributed Cloud Edge Cluster. For external-facing Distributed Cloud Edge Services, see Load balancing.

You must ensure that:

  • The Distributed Cloud Edge Pod CIDR block and the Distributed Cloud Edge Service CIDR block must not conflict with each other or with any other CIDR blocks on your local network.
  • The Distributed Cloud Edge Node CIDR block must not conflict with the Distributed Cloud Edge management CIDR blocks.
  • Distributed Cloud Edge load balancer virtual IP pools must not conflict across Distributed Cloud Edge Clusters.
  • If you are connecting to Virtual Private Cloud using Cloud VPN, the Pod and Service CIDR blocks must not conflict with any CIDR blocks on your VPC network.

Distributed Cloud Edge automatically allocates portions of the specified Distributed Cloud Edge Pod CIDR block as fixed-size Pod sub-CIDR blocks for each Node in the Zone based on the Node's configured maximum Pod count. By default, Distributed Cloud Edge sets the maximum Pod count per Node to 128, which results in the allocation of a /24 CIDR block per Node. You can change this count using the default-max-pods-per-node flag and Distributed Cloud Edge will automatically scale the Pod CIDR size based on the value you specify.

The following table lists the Pods-per-Node counts and their corresponding CIDR sizes:

Maximum Pods per Node IPv4 Pod CIDR block size
32 /26
33-64 /25
65-128 /24
129-256 /23

After you have created the Distributed Cloud Edge Cluster, you cannot modify the CIDR block and Pods-per-Node values described in this section. You must delete and recreate the Cluster with the new values.