Table Of Contents


User Guide

First time using the AWS CLI? See the User Guide for help getting started.

[ aws . elb ]



Adds the specified instances to the specified load balancer.

The instance must be a running instance in the same network as the load balancer (EC2-Classic or the same VPC). If you have EC2-Classic instances and a load balancer in a VPC with ClassicLink enabled, you can link the EC2-Classic instances to that VPC and then register the linked EC2-Classic instances with the load balancer in the VPC.

Note that RegisterInstanceWithLoadBalancer completes when the request has been registered. Instance registration takes a little time to complete. To check the state of the registered instances, use DescribeLoadBalancers or DescribeInstanceHealth .

After the instance is registered, it starts receiving traffic and requests from the load balancer. Any instance that is not in one of the Availability Zones registered for the load balancer is moved to the OutOfService state. If an Availability Zone is added to the load balancer later, any instances registered with the load balancer move to the InService state.

To deregister instances from a load balancer, use DeregisterInstancesFromLoadBalancer .

For more information, see Register or De-Register EC2 Instances in the Classic Load Balancers Guide .

See also: AWS API Documentation

See 'aws help' for descriptions of global parameters.


--load-balancer-name <value>
--instances <value>
[--cli-input-json <value>]
[--generate-cli-skeleton <value>]


--load-balancer-name (string)

The name of the load balancer.

--instances (list)

The IDs of the instances.

Shorthand Syntax:

--instances InstanceId1 InstanceId2 InstanceId3

JSON Syntax:

    "InstanceId": "string"

--cli-input-json (string) Performs service operation based on the JSON string provided. The JSON string follows the format provided by --generate-cli-skeleton. If other arguments are provided on the command line, the CLI values will override the JSON-provided values. It is not possible to pass arbitrary binary values using a JSON-provided value as the string will be taken literally.

--generate-cli-skeleton (string) Prints a JSON skeleton to standard output without sending an API request. If provided with no value or the value input, prints a sample input JSON that can be used as an argument for --cli-input-json. If provided with the value output, it validates the command inputs and returns a sample output JSON for that command.

See 'aws help' for descriptions of global parameters.


To register instances with a load balancer

This example registers the specified instance with the specified load balancer.


aws elb register-instances-with-load-balancer --load-balancer-name my-load-balancer --instances i-d6f6fae3


   "Instances": [
           "InstanceId": "i-d6f6fae3"
           "InstanceId": "i-207d9717"
           "InstanceId": "i-afefb49b"


Instances -> (list)

The updated list of instances for the load balancer.


The ID of an EC2 instance.

InstanceId -> (string)

The instance ID.