ELB
Elastic Load Balancing
Last updated
Elastic Load Balancing
Last updated
• Load balancers are servers that forward internet traffic to multiple servers (EC2 Instances) downstream.
• Spread load across multiple downstream instances
• Expose a single point of access (DNS) to your application
• Seamlessly handle failures of downstream instances
• Do regular health checks on your instances
• Provide SSL termination (HTTPS) for your websites
• High availability across zones
• An ELB (Elastic Load Balancer) is a managed load balancer
AWS guarantees that it will be working
AWS takes care of upgrades, maintenance, and high availability
AWS provides only a few configuration knobs
• It costs less to set your own load balancer but it will be a lot more effort on your end (maintenance, integrations)
• 4 kinds of load balancers offered by AWS:
Application Load Balancer (HTTP / HTTPS only) – Layer 7
Network Load Balancer (ultra-high performance, allows for TCP) – Layer 4
Gateway Load Balancer – Layer 3
Classic Load Balancer (retired in 2023) – Layers 4 & 7
