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Visual Walkthrough · Amazon EKS networking

How Prefix Delegation and Custom Networking Work on Amazon EKS

Follow web-30, a Pod in node group ng-web, until it gets an IP, then check yourself with 8 questions.

1Visual Walkthrough

An EKS node's ENIs, its subnet split into /28 blocks, and a secondary Pod CIDR with ENIConfigs A VPC with private subnet 10.0.1.0/24 holding an m5.large node with three ENIs, the aws-node agent and its settings, and a map of the subnet as 16 /28 blocks; a secondary CIDR 100.64.0.0/16 with a Pod subnet; ENIConfig objects per zone; the EC2 API and the internet. The walkthrough follows the Pod web-30: node-1 out of IPs, prefix delegation on node-2, no whole /28 left in the subnet, custom networking on node-3, and SNAT to the node's IP. EC2 API assigns IPs and /28 prefixes Internet api.example.com via the NAT gateway PRIVATE SUBNET 10.0.1.0/24 · us-east-1a aws-node networking agent P P P 1616161616161616 ContainerCreating 10.0.1.0/24 AS 16 BLOCKS OF /28 RESERVED · 10.0.1.128/25 SECONDARY CIDR 100.64.0.0/16 + 100.64.32.0/19 in us-east-1b POD SUBNET 100.64.0.0/19 · 1a 8,187 usable IPs holds Pod ENIs only, no nodes web-30 100.64.0.37 K8S API capacity ENIConfig us-east-1aPod subnet:100.64.0.0/19 ENIConfig us-east-1bPod subnet:100.64.32.0/19

    2Quiz to check understanding

    Check yourself