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Tencent Kubernetes Engine (TKE) provides different network modes for different scenarios. This document gives a detailed description of the GlobalRouter and VPC-CNI network modes, as well as comparisons on use cases, advantages, and use limits. You can select a network mode based on your business needs.

GlobalRouter Mode

GlobalRouter is a global routing capability provided by TKE based on the underlying VPC instance. It implements a routing policy for mutual access between the container network and the VPC instance. This network mode has the following characteristics:

• Container routing is performed directly through the VPC instance.
• Containers and nodes are located on the same network plane.
• Container IP ranges are dynamically assigned without occupying other IP ranges in the VPC instance.

The GlobalRouter mode is suitable for general use cases and can be seamlessly used with standard Kubernetes features. The following diagram illustrates how it works.

VPC-CNI Mode

VPC-CNI is a container network capability provided by TKE based on CNIs and VPC ENIs. It is suitable for scenarios with high latency requirements. In this network mode, containers and nodes are located on the same network plane, and container IP addresses are ENI IP addresses assigned by the IPAMD component.

The following diagram illustrates how the VPC-CNI mode works.

Enabling support for static pod IP addresses

Note：

• By default, the VPC-CNI mode does not support static pod IP addresses. You can set this capability only when creating a cluster and cannot modify it after the cluster is created.
• When support for static pod IP addresses is enabled, you can only choose an empty subnet to set up the cluster network.
• Pods with static IP addresses cannot be migrated across subnets.

In the step where you configure "Cluster Information", select VPC-CNI for "Container Network Add-on" and select "Enable Support" for "Static Pod IP", as shown below.

For information on how to use the VPC-CNI mode with static pod IP addresses, please see Managing StatefulSets with Static IP Addresses.

Choosing a Network Mode

This section compares the GlobalRouter and VPC-CNI network modes in terms of the use cases, advantages, and use limits. You can choose the network mode that best fits your needs.