Creating an ELB Ingress on the Console

Prerequisites

• An ingress provides network access for backend workloads. Ensure that a workload is available in a cluster. If no workload is available, deploy a workload by referring to Creating a Deployment, Creating a StatefulSet, or Creating a DaemonSet.
• Services Supported by Ingresses lists the Service types supported by ELB ingresses.

Constraints

• It is recommended that other resources not use the load balancer automatically created by an ingress. Otherwise, the load balancer will be occupied when the ingress is deleted, resulting in residual resources.
• After an ingress is created, upgrade and maintain the configuration of the selected load balancers on the CCE console. Do not modify the configuration on the ELB console. Otherwise, the ingress service may be abnormal.
• The URL registered in an ingress forwarding policy must be the same as the URL used to access the backend Service. Otherwise, a 404 error will be returned.
• In a cluster using the IPVS proxy mode, if the ingress and Service use the same ELB load balancer, the ingress cannot be accessed from the nodes and containers in the cluster because kube-proxy mounts the LoadBalancer Service address to the ipvs-0 bridge. This bridge intercepts the traffic of the load balancer connected to the ingress. Use different load balancers for the ingress and Service.
• Do not connect an Ingress and a Service using HTTP to the same listener of the same load balancer. Otherwise, a port conflict occurs.
• Dedicated load balancers must be the application type (HTTP/HTTPS) supporting private networks (with a private IP).
• If multiple ingresses access the same ELB port in a cluster, the listener configuration items (such as the certificate associated with the listener and the HTTP2 attribute of the listener) are subject to the configuration of the first ingress.

Adding an ELB Ingress

This section uses an Nginx workload as an example to describe how to add an ELB ingress.

1. Log in to the CCE console and click the cluster name to access the cluster console.
2. Choose Services & Ingresses in the navigation pane, click the Ingresses tab, and click Create Ingress in the upper right corner.
3. Configure ingress parameters.
   • Name: specifies a name of an ingress, for example, ingress-demo.
   • Interconnect with Nginx: This option is displayed only after the Nginx Ingress Controller add-on is installed. If this option is available, the nginx-ingress add-on has been installed. Enabling this option will create an Nginx ingress. Disable it if you want to create an ELB ingress. For details, see Creating Nginx Ingresses on the Console.
   • Load Balancer

     Select the load balancer to interconnect. Only load balancers in the same VPC as the cluster are supported. If no load balancer is available, click Create Load Balancer to create one on the ELB console.

     Dedicated load balancers must support HTTP or HTTPS and the network type must support private networks.

     The CCE console supports automatic creation of load balancers. Select Auto create from the drop-down list box and configure the following parameters:

     • Instance Name: Enter a load balancer name.
     • Public Access: If enabled, an EIP with 5 Mbit/s bandwidth will be created. By default, it is billed by traffic.
     • Subnet, AZ, and Specifications (available only for dedicated load balancers): Configure the subnet, AZ, and specifications. Only dedicated load balancers of the application type (HTTP/HTTPS) can be automatically created.
   • Listener: Ingress configures a listener for the load balancer, which listens to requests from the load balancer and distributes traffic. After the configuration is complete, a listener is created on the load balancer. The default listener name is k8s__<Protocol type>_<Port number>, for example, k8s_HTTP_80.
     • External Protocol: HTTP and HTTPS are available.
     • External Port: Port number that is open to the ELB service address. The port number can be specified randomly.
     • Certificate Source: TLS secret and ELB server certificate are supported.
     • Server Certificate: When an HTTPS listener is created for a load balancer, bind a certificate to the load balancer to support encrypted authentication for HTTPS data transmission.
       • TLS secret: For details about how to create a secret certificate, see Creating a Secret.
       • ELB server certificate: Use the certificate created in the ELB service.
       

       If there is already an HTTPS ingress for the chosen port on the load balancer, the certificate of the new HTTPS ingress must be the same as the certificate of the existing ingress. This means that a listener has only one certificate. If two certificates, each with a different ingress, are added to the same listener of the same load balancer, only the certificate added earliest takes effect on the load balancer.

     • SNI: Server Name Indication (SNI) is an extended protocol of TLS. It allows multiple TLS-based access domain names to be provided for external systems using the same IP address and port. Different domain names can use different security certificates. After SNI is enabled, the client is allowed to submit the requested domain name when initiating a TLS handshake request. After receiving the TLS request, the load balancer searches for the certificate based on the domain name in the request. If the certificate corresponding to the domain name is found, the load balancer returns the certificate for authorization. Otherwise, the default certificate (server certificate) is returned for authorization.
       

       • The SNI option is available only when HTTPS is selected.

       • This function is supported only in clusters of v1.15.11 and later.
       • Specify the domain name for the SNI certificate. Only one domain name can be specified for each certificate. Wildcard-domain certificates are supported.
     • Security Policy: combinations of different TLS versions and supported cipher suites available to HTTPS listeners.

       For details about security policies, see Security Policy.

       

       • Security Policy is available only when HTTPS is selected.
       • This function is supported only in clusters of v1.17.9 and later.
     • Backend Protocol:

       When the listener is HTTP-compliant, only HTTP can be selected.

       If it is an HTTPS listener, this parameter can be set to HTTP, gRPC, or HTTPS. Only dedicated load balancers support gRPC. After HTTP/2 is enabled, CCE will automatically add the kubernetes.io/elb.http2-enable:true annotation. gRPC is available only in certain regions. For details, see the CCE console.

   • Forwarding Policy: When the access address of a request matches the forwarding policy (a forwarding policy consists of a domain name and URL, for example, 10.117.117.117:80/helloworld), the request is forwarded to the corresponding target Service for processing. You can click to add multiple forwarding policies.
     • Domain Name: actual domain name. Ensure that the domain name has been registered and archived. Once a domain name rule is configured, you must use the domain name for access.
     • URL Matching Rule
       • Prefix match: If the URL is set to /healthz, the URL that meets the prefix can be accessed, for example, /healthz/v1 and /healthz/v2.
       • Exact match: The URL can be accessed only when it is fully matched. For example, if the URL is set to /healthz, only /healthz can be accessed.
       • RegEX match: The URL is matched based on the regular expression. For example, if the regular expression is /[A-Za-z0-9_.-]+/test, all URLs that comply with this rule can be accessed, for example, /abcA9/test and /v1-Ab/test. Two regular expression standards are supported: POSIX and Perl.
     • URL: access path to be registered, for example, /healthz.
       

       The access path added here must exist in the backend application. Otherwise, the forwarding fails.

       For example, the default access URL of the Nginx application is /usr/share/nginx/html. When adding /test to the ingress forwarding policy, ensure the access URL of your Nginx application contains /usr/share/nginx/html/test. Otherwise, error 404 will be returned.

     • Destination Service: Select an existing Service or create a Service. Services that do not meet search criteria are automatically filtered out.
     • Destination Service Port: Select the access port of the destination Service.
     • Set ELB:
       • Algorithm: Three algorithms are available: weighted round robin, weighted least connections algorithm, or source IP hash.
         

         • Weighted round robin: Requests are forwarded to different servers based on their weights, which indicate server processing performance. Backend servers with higher weights receive proportionately more requests, whereas equal-weighted servers receive the same number of requests. This algorithm is often used for short connections, such as HTTP services.
         • Weighted least connections: In addition to the weight assigned to each server, the number of connections processed by each backend server is considered. Requests are forwarded to the server with the lowest connections-to-weight ratio. Building on least connections, the weighted least connections algorithm assigns a weight to each server based on their processing capability. This algorithm is often used for persistent connections, such as database connections.
         • Source IP hash: The source IP address of each request is calculated using the hash algorithm to obtain a unique hash key, and all backend servers are numbered. The generated key allocates the client to a particular server. This enables requests from different clients to be distributed in load balancing mode and ensures that requests from the same client are forwarded to the same server. This algorithm applies to TCP connections without cookies.
       • Sticky Session: This function is disabled by default. Options are as follows:
         • Load balancer cookie: Enter the Stickiness Duration , which ranges from 1 to 1,440 minutes.
         • Application cookie: This parameter is available only for shared load balancers. In addition, enter Cookie Name, which ranges from 1 to 64 characters.
         

         • When the distribution policy uses the source IP hash, sticky session cannot be set.
         • Dedicated load balancers in the clusters of a version earlier than v1.21 do not support sticky sessions. If sticky sessions are required, use shared load balancers.
       • Health Check: Set the health check configuration of the load balancer. If this function is enabled, the following configurations are supported:

         Parameter	Description
         Protocol	When the protocol of the target Service port is TCP, TCP, gRPC, and HTTP protocols are supported. Only dedicated load balancers support gRPC. gRPC is available only in certain regions. For details, see the CCE console. Check Path (supported by HTTP or gRPC for health check): specifies the health check URL. The check path must start with a slash (/) and contain 1 to 80 characters.
         Port	By default, the service port (NodePort or container port of the Service) is used for health check. You can also specify another port for health check. After the port is specified, a service port named cce-healthz will be added for the Service. Node Port: If a shared load balancer is used or no ENI instance is associated, the node port is used as the health check port. If this parameter is not specified, a random port is used. The value ranges from 30000 to 32767. Container Port: When a dedicated load balancer is associated with an ENI instance, the container port is used for health check. The value ranges from 1 to 65535.
         Check Period (s)	Specifies the maximum interval between health checks. The value ranges from 1 to 50.
         Timeout (s)	Specifies the maximum timeout duration for each health check. The value ranges from 1 to 50.
         Max. Retries	Specifies the maximum number of health check retries. The value ranges from 1 to 10.

     • Operation: Click Delete to delete the configuration.
   • Annotation: Ingresses provide some advanced CCE functions, which are implemented by annotations. When you use kubectl to create a container, annotations will be used. For details, see Creating an Ingress - Automatically Creating a Load Balancer and Creating an Ingress - Interconnecting with an Existing Load Balancer.

4. After the configuration is complete, click OK. After the ingress is created, it is displayed in the ingress list.

   On the ELB console, you can view the ELB automatically created through CCE. The default name is cce-lb-ingress.UID. Click the ELB name to access its details page. On the Listeners tab page, view the route settings of the ingress, including the URL, listener port, and backend server group port.

   

   After an ingress is created, upgrade and maintain the selected load balancer on the CCE console. Do not modify the configuration on the ELB console. Otherwise, the ingress service may be abnormal.

   Figure 1 ELB routing configuration
   

5. Access the /healthz interface of the workload, for example, workload defaultbackend.
   1. Obtain the access address of the /healthz interface of the workload. The access address consists of the load balancer IP address, external port, and mapping URL, for example, 10.**.**.**:80/healthz.
   2. Enter the URL of the /healthz interface, for example, http://10.**.**.**:80/healthz, in the address box of the browser to access the workload, as shown in Figure 2.
      Figure 2 Accessing the /healthz interface of defaultbackend
      

Related Operations

The Kubernetes ingress structure does not contain the property field. Therefore, the ingress created by the API called by client-go does not contain the property field. CCE provides a solution to ensure compatibility with the Kubernetes client-go. For details about the solution, see How Can I Achieve Compatibility Between Ingress's property and Kubernetes client-go?