Adding or Deleting Listeners

You can add one or more listeners to a load balancer and remove them at any time if you no longer need them. Adding a listener to a load balancer enables it to listen to inbound flows on a specified port and in a specified protocol, and to send the traffic load to backend virtual machines (VMs) using a specified port and protocol.

As you can configure only one health check type per load balancer specifying the backend VMs port and protocol to check, we strongly recommend to create one load balancer per service to avoid any undetected failure, meaning that your listeners should all send the traffic load to backend VMs using the same port and protocol.

You cannot modify an existing listener. The only way to modify the port and protocol on the load balancer’s side or on the backend VMs' side is to add a listener with the corresponding configuration, and remove the former one if needed.

Adding or Deleting Listeners Using OSC CLI

Adding a Listener to a Load Balancer

The CreateLoadBalancerListeners command creates one or more listeners for a specified load balancer.

For more information, see About Load Balancers.

Request sample

$ osc-cli api CreateLoadBalancerListeners --profile "default" \
    --LoadBalancerName "example-lbu" \
    --Listeners '[
        {
          "BackendPort": 58,
          "BackendProtocol": "TCP",
          "LoadBalancerPort": 62,
          "LoadBalancerProtocol": "TCP",
        },
      ]'

This command contains the following attributes that you need to specify:

DryRun: (optional) If true, checks whether you have the required permissions to perform the action.
Listeners: One or more listeners for the load balancer.
LoadBalancerName: The name of the load balancer for which you want to create listeners.

The CreateLoadBalancerListeners command returns the following elements:

LoadBalancer: Information about the load balancer.
ResponseContext: Information about the context of the response.

Result sample

{
  "ResponseContext": {
    "RequestId": "0475ca1e-d0c5-441d-712a-da55a4175157"
  },
  "LoadBalancer": {
    "Tags": [],
    "SourceSecurityGroup": {
      "SecurityGroupName": "security-group-example",
      "SecurityGroupAccountId": "123456789012"
    },
    "SecuredCookies": false,
    "Subnets": [
      "subnet-12345678"
    ],
    "NetId": "vpc-12345678",
    "BackendVmIds": [],
    "ApplicationStickyCookiePolicies": [],
    "SecurityGroups": [
      "sg-12345678"
    ],
    "LoadBalancerType": "internal",
    "AccessLog": {
      "PublicationInterval": 60,
      "IsEnabled": false
    },
    "DnsName": "internal-example-lbu.123456789.eu-west-2.lbu.outscale.com",
    "HealthCheck": {
      "UnhealthyThreshold": 2,
      "Timeout": 5,
      "CheckInterval": 30,
      "Protocol": "TCP",
      "HealthyThreshold": 10,
      "Port": 80
    },
    "LoadBalancerStickyCookiePolicies": [],
    "SubregionNames": [
      "eu-west-2a"
    ],
    "Listeners": [
      {
        "BackendPort": 58,
        "BackendProtocol": "TCP",
        "LoadBalancerPort": 62,
        "LoadBalancerProtocol": "TCP"
      },
      {
        "BackendPort": 80,
        "BackendProtocol": "TCP",
        "LoadBalancerPort": 80,
        "LoadBalancerProtocol": "TCP"
      }
    ],
    "LoadBalancerName": "example-lbu"
  }
}

Deleting a Listener from a Load Balancer

The DeleteLoadBalancerListeners command deletes listeners of a specified load balancer.

Request sample

$ osc-cli api DeleteLoadBalancerListeners --profile "default" \
    --LoadBalancerName "example-lbu" \
    --LoadBalancerPorts '[80]'

This command contains the following attributes that you need to specify:

DryRun: (optional) If true, checks whether you have the required permissions to perform the action.
LoadBalancerName: The name of the load balancer for which you want to delete listeners.
LoadBalancerPorts: One or more port numbers of the listeners you want to delete.

The DeleteLoadBalancerListeners command returns the following elements:

LoadBalancer: Information about the load balancer.
ResponseContext: Information about the context of the response.

Result sample

{
  "ResponseContext": {
    "RequestId": "0475ca1e-d0c5-441d-712a-da55a4175157"
  },
  "LoadBalancer": {
    "Tags": [],
    "SourceSecurityGroup": {
      "SecurityGroupName": "security-group-example",
      "SecurityGroupAccountId": "123456789012"
    },
    "SecuredCookies": false,
    "Subnets": [
      "subnet-12345678"
    ],
    "NetId": "vpc-12345678",
    "BackendVmIds": [],
    "ApplicationStickyCookiePolicies": [],
    "SecurityGroups": [
      "sg-12345678"
    ],
    "LoadBalancerType": "internal",
    "AccessLog": {
      "PublicationInterval": 60,
      "IsEnabled": false
    },
    "DnsName": "internal-example-lbu.123456789.eu-west-2.lbu.outscale.com",
    "HealthCheck": {
      "UnhealthyThreshold": 2,
      "Timeout": 5,
      "CheckInterval": 30,
      "Protocol": "TCP",
      "HealthyThreshold": 10,
      "Port": 80
    },
    "LoadBalancerStickyCookiePolicies": [],
    "SubregionNames": [
      "eu-west-2a"
    ],
    "Listeners": [],
    "LoadBalancerName": "example-lbu"
  }
}