Creating a backend group

If you do not have the Yandex Cloud command line interface yet, install and initialize it.

The folder specified in the CLI profile is used by default. You can specify a different folder using the --folder-name or --folder-id parameter.

1. View the description of the CLI command to create a backend group:

   yc alb backend-group create --help
   

2. Create a backend group by running the command:

   yc alb backend-group create <backend_group_name>
   

   Result:

   id: a5dg2cv4ngne********
   name: test-backend-group
   folder_id: aoerb349v3h4********
   created_at: "2021-02-11T20:46:21.688940670Z"
   

3. Add a backend and health check to the group.

   Alert

   If all backends in an availability zone with health checks enabled fail the checks, traffic will stop routing to the zone, even if there are working backends without health checks in the zone.

   We recommend configuring health checks for all backends.

   All backends within the group must be of the same type: HTTP, gRPC, or Stream.

   HTTP backend

   Run this command:

   yc alb backend-group add-http-backend \
     --backend-group-name <backend_group_name> \
     --name <name_of_backend_being_added> \
     --weight <backend_weight> \
     --port <backend_port> \
     --target-group-id=<target_group_ID> \
     --panic-threshold 90 \
     --http-healthcheck port=80,healthy-threshold=10,unhealthy-threshold=15,\
   timeout=10s,interval=2s,host=<host_address>,path=<path>
   

   Where:

   • --panic-threshold: Panic mode threshold
   • --http-healthcheck: Resource health check parameters:
     • port: Port
     • healthy-threshold: Healthy threshold
     • unhealthy-threshold: Unhealthy threshold
     • timeout: Timeout
     • interval: Interval
     • host: Host address
     • path: Path

   Result:

   id: a5dqkr2mk3rr********
   name: <backend_group_name>
   folder_id: aoe197919j8e********
   http:
     backends:
     - name: <backend_name>
       backend_weight: "1"
       load_balancing_config:
         panic_threshold: "90"
       port: "80"
       target_groups:
         target_group_ids:
         - a5d2iap3nue9********
       healthchecks:
       - timeout: 10s
         interval: 2s
         healthy_threshold: "10"
         unhealthy_threshold: "15"
         healthcheck_port: "80"
         http:
           host: <host_address>
           path: <path>
   created_at: "2021-02-11T20:46:21.688940670Z"
   

   gRPC backend

   Run this command:

   yc alb backend-group add-grpc-backend \
     --backend-group-name <backend_group_name> \
     --name <name_of_backend_being_added> \
     --weight <backend_weight> \
     --port <backend_port> \
     --target-group-id=<target_group_ID> \
     --panic-threshold 90 \
     --grpc-healthcheck port=80,healthy-threshold=10,unhealthy-threshold=15,\
   timeout=10s,interval=2s,service-name=<gRPC_service_name>
   

   Where:

   • --panic-threshold: Panic mode threshold.
   • --grpc-healthcheck: Resource health check parameters:
     • port: Port.
     • healthy-threshold: Healthy threshold.
     • unhealthy-threshold: Unhealthy threshold.
     • timeout: Timeout.
     • interval: Interval.
     • service-name: Name of the gRPC service to check. If no service is specified, the backend general health is checked.

   Result:

   id: a5dqkr2mk3rr********
   name: <backend_group_name>
   folder_id: aoe197919j8e********
   grpc:
     backends:
       - name: <backend_name>
         backend_weight: "12"
         load_balancing_config:
           panic_threshold: "90"
         port: "80"
         target_groups:
           target_group_ids:
             - a5d2iap3nue9********
         healthchecks:
           - timeout: 10s
             interval: 2s
             healthy_threshold: "10"
             unhealthy_threshold: "15"
             healthcheck_port: "80"
             grpc:
               service_name: <gRPC_service_name>
   created_at: "2023-06-17T13:04:08.567141292Z"
   

   Stream backend

   Run this command:

   yc alb backend-group add-stream-backend \
     --backend-group-name <backend_group_name> \
     --name <name_of_backend_to_add> \
     --weight <backend_weight> \
     --port <backend_port> \
     --target-group-id=<target_group_ID> \
     --panic-threshold 90 \
     --enable-proxy-protocol \
     --stream-healthcheck port=80,healthy-threshold=10,unhealthy-threshold=15,\
   timeout=10s,interval=2s,send-text=<data_to_endpoint>,receive-text=<data_from_endpoint>
   

   Where:

   • --panic-threshold: Panic mode threshold.
   • --enable-proxy-protocol: If this option is enabled, the load balancer will send metadata about its connection to the client, including its IP, to the backend over the PROXY protocol from HAProxy. If this option is not specified, only the load balancer's IP address will be provided to the backend.
   • --stream-healthcheck: Resource health check parameters:
     • port: Port.
     • healthy-threshold: Healthy threshold.
     • unhealthy-threshold: Unhealthy threshold.
     • timeout: Timeout.
     • interval: Interval.
     • send-text: Data to send to the endpoint for a health check.
     • receive-text: Data to receive from the endpoint for it to pass the health check.

   Result:

   id: ds77tero4f5********
   name: <backend_group_name>
   folder_id: b1gu6g9ielh6********
   stream:
     backends:
     - name: <backend_name>
   backend_weight: "1"
       port: "80"
       target_groups:
         target_group_ids:
         - ds7eof3r2cte********
       healthchecks:
         - timeout: 10s
           interval: 2s
           healthy_threshold: "10"
           unhealthy_threshold: "15"
           healthcheck_port: "80"
           stream:
             send:
               text: <data_to_endpoint>
             receive:
               text: <data_from_endpoint>
       enable_proxy_protocol: true
   created_at: "2022-04-06T09:17:57.104324513Z"
   

With Terraform, you can quickly create a cloud infrastructure in Yandex Cloud and manage it using configuration files. These files store the infrastructure description written in HashiCorp Configuration Language (HCL). If you change the configuration files, Terraform automatically detects which part of your configuration is already deployed, and what should be added or removed.

Terraform is distributed under the Business Source License. The Yandex Cloud provider for Terraform is distributed under the MPL-2.0 license.

For more information about the provider resources, see the documentation on the Terraform website or mirror website.

If you don't have Terraform, install it and configure the Yandex Cloud provider.

1. In the Terraform configuration file, describe the parameters of the resource to create:

   resource "yandex_alb_backend_group" "test-backend-group" {
     name                     = "<backend_group_name>"
     session_affinity {
       connection {
         source_ip = <IP_address_session_affinity_mode>
       }
     }
     stream_backend {
       name                   = "<backend_name>"
       weight                 = 1
       port                   = 80
       target_group_ids       = ["<target_group_ID>"]
       load_balancing_config {
         panic_threshold      = 90
       }
       enable_proxy_protocol  = true
       healthcheck {
         timeout              = "10s"
         interval             = "2s"
         healthy_threshold    = 10
         unhealthy_threshold  = 15
         stream_healthcheck {
           send               = "<data_to_endpoint>"
           receive            = "<data_from_endpoint>"
         }
       }
     }
   }
   

   Where:

   • yandex_alb_backend_group: Backend group parameters:

     • name: Backend group name.

     • session_affinity: Session affinity settings. This is an optional parameter.

       Note

       Currently, session affinity only works if a single backend is active (has a positive weight) in a group of backends, includes one or more target groups, and the MAGLEV_HASH load balancing mode is selected for it.

       • connection: Mode of session affinity by IP address (source_ip). It can either be true or false. The cookie and header modes are also available. Only one of the modes should be specified. If the backend group is of the Stream type (consists of the stream_backend resources), you can only use the connection mode for session affinity.

     • http_backend, grpc_backend, and stream_backend: Backend type. All backends within the group must be of the same type: HTTP, gRPC, or Stream.

   Backend parameters:

   • name: Backend name.

   • port: Backend port.

   • weight: Backend weight.

   • target_group_ids: Target group ID. To get a list of available target groups, run the following CLI command: yc alb target-group list.

   • load_balancing_config: Balancing parameters:

     • panic_threshold: Panic mode threshold.

   • enable_proxy_protocol: With this option enabled, the load balancer will send metadata about its connection to the client, including its IP, to the backend over the PROXY protocol from HAProxy. If the option is not specified, only the load balancer's IP address will be provided to the backend. This parameter is only available for Stream type backends.

   • healthcheck: Health check parameters:

     • timeout: Timeout.
     • interval: Interval.
     • healthy_threshold: Healthy threshold.
     • unhealthy_threshold: Unhealthy threshold.
     • http_healthcheck: HTTP health check parameters:
       • path: Path.
       • host: Host address.
     • grpc_healthcheck: gRPC health check parameters:
       • service_name: Name of the gRPC service to be checked. If no service is specified, the backend general health is checked.
     • stream_healthcheck: Stream health check parameters:
       • send: Data to send to the endpoint for a health check.
       • receive: Data to receive from the endpoint for it to pass the health check.

     Alert

     If all backends in an availability zone with health checks enabled fail the checks, traffic will stop routing to the zone, even if there are working backends without health checks in the zone.

     We recommend configuring health checks for all backends.

   For more information about the yandex_alb_backend_group resource properties, see the Terraform provider documentation.

2. Create resources:

   1. In the terminal, change to the folder where you edited the configuration file.

   2. Make sure the configuration file is correct using the command:

      terraform validate
      

      If the configuration is correct, the following message is returned:

      Success! The configuration is valid.
      

   3. Run the command:

      terraform plan
      

      The terminal will display a list of resources with parameters. No changes are made at this step. If the configuration contains errors, Terraform will point them out.

   4. Apply the configuration changes:

      terraform apply
      

   5. Confirm the changes: type yes in the terminal and press Enter.

   Terraform will create all the required resources. You can check the new resources using the management console or this CLI command:

   yc alb backend-group list
   

Use the create REST API method for the BackendGroup resource or the BackendGroupService/Create gRPC API call.