AWS Elastic Load Balancing (ALB vs. NLB)

Learn ALB (Layer 7) and NLB (Layer 4) load balancers, target groups, health checks, and routing strategies for high availability.

elb-config.json
{
"LoadBalancer": {
"Type": "ALB",
"TargetGroup": "web-targets",
"HealthCheck": "enabled"
}
}
elb-config.json
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Tutor:Elastic Load Balancing (ELB) automatically distributes incoming application traffic across multiple targets, such as EC2 instances, containers, and IP addresses, in one or more Availability Zones.


ELB Mastery

Unlock nodes by learning new load balancing concepts.

Concept 1: ELB Basics

Elastic Load Balancing (ELB) automatically distributes incoming application traffic across multiple targets, such as EC2 instances, containers, and IP addresses, in one or more Availability Zones. ELB improves application availability and fault tolerance.

System Check

What does ELB automatically distribute?

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AWS Elastic Load Balancing (ALB vs. NLB)

Author

Pascual Vila

Cloud Instructor.

Elastic Load Balancing (ELB) automatically distributes incoming application traffic across multiple targets, such as EC2 instances, containers, and IP addresses, in one or more Availability Zones.

Load Balancer Types

AWS offers three types of load balancers: Application Load Balancer (ALB) operates at Layer 7, Network Load Balancer (NLB) operates at Layer 4, and Classic Load Balancer (CLB) is the legacy option. ALB is best for HTTP/HTTPS traffic, while NLB is best for TCP/UDP traffic.

ALB Features

Application Load Balancer (ALB) supports content-based routing, host-based routing, path-based routing, and query string routing. ALB can route requests to different target groups based on the content of the request.

NLB Features

Network Load Balancer (NLB) operates at Layer 4 and can handle millions of requests per second with ultra-low latency. NLB is ideal for TCP/UDP traffic and can preserve the source IP address of the client.

Elastic Load Balancing Glossary

Elastic Load Balancing (ELB)
Automatically distributes incoming application traffic across multiple targets, such as EC2 instances, containers, and IP addresses, in one or more Availability Zones.
Application Load Balancer (ALB)
Operates at Layer 7 (HTTP/HTTPS). Supports content-based routing, host-based routing, path-based routing, and query string routing. Best for HTTP/HTTPS applications.
Network Load Balancer (NLB)
Operates at Layer 4 (TCP/UDP). Can handle millions of requests per second with ultra-low latency. Best for TCP/UDP traffic requiring high performance.
Target Group
Routes requests to registered targets. ALB supports instance targets, IP targets, and Lambda function targets. NLB supports instance targets and IP targets.
Health Check
Monitors the health of registered targets. Determines if targets are available to receive traffic. Unhealthy targets are automatically removed from routing.