Elastic Load Balancing

Overview

CloudMock emulates Elastic Load Balancing v2 (ALB/NLB), supporting load balancers, target groups, listeners, rules, target health, and tagging.

Supported Operations

Operation	Status	Notes
CreateLoadBalancer	Supported	Creates an ALB or NLB
DescribeLoadBalancers	Supported	Lists load balancers
DeleteLoadBalancer	Supported	Deletes a load balancer
ModifyLoadBalancerAttributes	Supported	Modifies LB attributes
CreateTargetGroup	Supported	Creates a target group
DescribeTargetGroups	Supported	Lists target groups
DeleteTargetGroup	Supported	Deletes a target group
ModifyTargetGroup	Supported	Modifies target group settings
RegisterTargets	Supported	Registers targets
DeregisterTargets	Supported	Deregisters targets
DescribeTargetHealth	Supported	Returns target health status
CreateListener	Supported	Creates a listener
DescribeListeners	Supported	Lists listeners
DeleteListener	Supported	Deletes a listener
ModifyListener	Supported	Modifies a listener
CreateRule	Supported	Creates a listener rule
DescribeRules	Supported	Lists listener rules
DeleteRule	Supported	Deletes a listener rule
AddTags	Supported	Adds tags to resources
RemoveTags	Supported	Removes tags from resources
DescribeTags	Supported	Lists tags for resources

Quick Start

Node.js

import { ElasticLoadBalancingV2Client, CreateLoadBalancerCommand } from '@aws-sdk/client-elastic-load-balancing-v2';

const client = new ElasticLoadBalancingV2Client({
  endpoint: 'http://localhost:4566',
  region: 'us-east-1',
  credentials: { accessKeyId: 'test', secretAccessKey: 'test' },
});

const { LoadBalancers } = await client.send(new CreateLoadBalancerCommand({
  Name: 'my-alb',
  Subnets: ['subnet-12345', 'subnet-67890'],
  Type: 'application',
}));
console.log(LoadBalancers[0].LoadBalancerArn);

Python

import boto3

client = boto3.client('elbv2',
    endpoint_url='http://localhost:4566',
    region_name='us-east-1',
    aws_access_key_id='test',
    aws_secret_access_key='test')

response = client.create_load_balancer(
    Name='my-alb',
    Subnets=['subnet-12345', 'subnet-67890'],
    Type='application')
print(response['LoadBalancers'][0]['LoadBalancerArn'])

Configuration

cloudmock.yml

services:
  elasticloadbalancing:
    enabled: true

Known Differences from AWS

• Load balancers do not route actual traffic
• Target health checks are simulated
• DNS names are generated but do not resolve