container network interface
Plan IP addressing for AKS configured with Azure CNI Networking
·328 words·2 mins
kubernetes
azure
aks
container network interface
cni
ip
When configuring Azure Kubernetes Service with Azure Container Network Interface (CNI), every pod gets an IP address of the subnet you’ve configured.
So how do you plan you address space? What factors should you consider?
Each node consumes one IP. Each pod consumes one IP. Each internal LoadBalancer Service you anticipate consumes one IP. Azure reserves 5 IP addresses within each subnet. The Max pods per node is 250. The Max pods per nodes lower limit is 10. 30 pods is the minimum per cluster. Max nodes per cluster is 1000. When a cluster is upgraded a new node is added as part of the process which requires a minimum of one additional block of IP addresses to be available. Your node count is then n + 1. When you scale a cluster an additional node is added. Your node count is then n + number-of-additional-scaled-nodes-you-anticipate + 1. With all that in mind the formula to calculate the number of IPs required for your cluster should look like this: