Kubernetes api service unit file i was going through the kubernetes the hard way(kelsey), i see in the API server unit file with a cluster ip range as 
 --service-cluster-ip-range=10.32.0.0/24 \
 is it a default ip range ?
my VPC CIDR is 172.31.0.0/16 this so should i need to provide this ip instead of default one ?
The --service-cluster-ip-range will define the range of IP address that Kubernetes will assign when you create a ClusterIP Service. It's different from your VPC CIDR which correspond to your nodes (EC2) IPs. You can let the default 10.32.0.0/24 as is or change it but make sure that it does not overlap with your VPC CIDR.