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Visual Walkthrough · Amazon EKS networking

How the VPC CNI Works on Amazon EKS

Follow shop's Pods on one node as the node, then the subnet, runs out of IPs, then check yourself with 8 questions.

1Visual Walkthrough

An EKS node's ENIs handing VPC IPs to Pods, with the subnet, a second Pod range and an RDS database A VPC with a private subnet holding node-1 (a t3.medium) with its aws-node agent, three ENIs and shop's Pods, plus a Pod subnet in a second VPC range and an RDS database. The walkthrough shows spare IPs, a Pod getting a VPC IP, a second ENI attached through the EC2 API, max pods at 17, prefix delegation raising it to 110, the subnet running out, custom networking, and the Pods' new security group being allowed by RDS. EC2 API attaches ENIs, assigns IPs VPC · 10.0.0.0/16 PRIVATE SUBNET 10.0.1.0/24 POD SUBNET 100.64.0.0/19 a second VPC range, set by ENIConfig node-1 · t3.medium · 10.0.1.10 aws-node CNI plugin + ipamd keeps spare IPs warm ENI 1 (primary) 10.0.1.10 · the node ENI 2 attached by ipamd ENI 3 attached by ipamd shop-1 10.0.1.15 shop-2 10.0.1.16 shop-3 10.0.1.41 shop-4 10.0.1.42 shop-1 100.64.0.21 shop-2 100.64.0.22 + 28 more shop Pods Amazon RDS 10.0.3.20:5432 allows the node security group

    2Quiz to check understanding

    Check yourself