GoLoadBalancer

Understanding the fundamental knowledge of load balancer. Layer 7 Load balancer for now(HTTP Levels), but I would like to make it works for the Layer 4, which is TCP/IP layer.

Load balancer setup

• Load balancer configuration setup requirements.

Health check

• Load balancer should check whether connected servers are available and healthy. Context from the AWS. https://docs.aws.amazon.com/elasticloadbalancing/latest/network/target-group-health-checks.html

Network Load Balancers use active and passive health checks to determine whether a target is available to handle requests. By default, each load balancer node routes requests only to the healthy targets in its Availability Zone. If you enable cross-zone load balancing, each load balancer node routes requests to the healthy targets in all enabled Availability Zones.

Health check status are: Initial, Healthy, Unhealthy, Draining, Unhealthy.draining, unavailable.

Algorithms

Round Robin

• Distribute incoming client requests across multiple servers in a sequential, cyclical manner.Each incoming request is forwarded to the next server, and it loops back to the first server when it hits the end of the server list.

Weighted Round Robin(In Progress)

• TBD

Reference

• https://medium.com/@leonardo5621_66451/building-a-load-balancer-in-go-1c68131dc0ef
• https://www.geeksforgeeks.org/how-do-you-load-balance-tcp-traffic/#importance-of-load-balancing-tcp-traffic