Introduction
This document describes how to use Service and Ingress as entry points to expose workloads to external sources.
Service Types
Service
Service defines policies for accessing backend Pods and provides a fixed virtual IP address for access. It also provides load balancing for all requests to Pods.
Service can be of the following types:
Public network access: the public network access Service uses operates in Loadbalance and automatically creates a public network CLB instance. Public IP addresses can access backend Pods.
Intra-cluster access: the intra-cluster access Service operates in ClusterIP mode and is used for access within the cluster.
VPC private network access: the VPC private network access Service operates in Loadbalance and automatically creates a private network CLB instance. By using annotations:service.kubernetes.io/qcloud-loadbalancer-internal-subnetid: subnet-xxxxxxxx, you can use a private IP address from the VPC private network to access the backend Pod.
Note:
When the service type is public network access, ClusterIP of this service is disabled by default. You can add the following annotations in yaml to enable ClusterIP:
service.kubernetes.io/qcloud-clusterip-loadbalancer-subnetid: #Subnet ID of the service CIDR
Ingress
Ingress is a collection of rules that allow access to Services of a cluster. You can configure different forwarding rules to allow different URLs to access different Services.
In order for Ingress resources to operate properly, you must run Ingress-controller. TKE enables the CLB-based l7-lb-controller by default and supports HTTP, HTTPS, and nginx-ingress controllers. You can select Ingress controllers according to your needs.
Prerequisites
You have created an serverless cluster that is in the Running state. For more information, see Creating a cluster. The cluster has an appropriate namespace that is in the Active state.
Directions
Considerations
Creating ClusterIP Service in an serverless cluster uses IP addresses from the Service CIDR. Make sure there are enough IP addresses in the subnet.
In an serverless cluster, a CLB instance created by the Service binds all ENIs of all Pods within the endpoint.
In an serverless cluster, Services only supports CLB instances. To create a Service using an existing CLB, you must ensure that the CLB is not bound to any listener.