EKS - IP definitions

The definition of IP ranges for EKS clusters can be confusing : pods , nodes and services.
Where are they getting their IPs from ?

EKS pods and nodes IP

Option 1 - VPC CIDR

Use the default VPC CIDR

Option 2 - secondary CIDR

It is possible to define additional different CIDR por the nodes and pods.

The CIDR should be using RFC1918 range :

10.0.0.0/8 
172.16.0.0.0/12
192.168.0.0/16   

See the instructions here

Additional ip ranges are also supported
The CIDR range are below:

100.64.0.0/10 
198.19.0.0/16	

100.64.0.0/10 is part of shared IP addresses

EKS services IP

Option 1

The range is set by AWS during EKS deploymnet , depanding on subnet range . This is actually subset of RFC1918 CIDR range:

10.100.0.0/16 
172.20.0.0/16

Option 2

It is possible to define custom service cluster ip .

Examples:

• Cloudformation
• Terraform
  In this case the RFC1918 CIDR range should be used :

  10.0.0.0/8 
  172.16.0.0.0/12
  192.168.0.0/16   
  

For more information on this feature is here