AWS Elastic Load Balancing vs Linux Virtual Server

AWS Elastic Load Balancing distributes incoming application traffic across targets and virtual appliances in one or more Availability Zones. It offers Application, Network, Gateway, and Classic Load Balancers, scales request handling with traffic, and runs configurable health checks on targets. Application Load Balancers support HTTP header-based routing, redirects, fixed responses, HTTP/2, and gRPC. Network Load Balancers support static Elastic IP addresses and AWS PrivateLink for TCP and TLS listeners. The service also supports SSL/TLS termination, certificate management, and client certificate authentication. CloudWatch metrics and logging are available for all four types. A single load balancer can distribute traffic across AWS and on-premises resources. Kubernetes support includes direct-to-pod routing for Application Load Balancers and private EKS clusters for Application and Network Load Balancers. AWS recommends different types for HTTP, transport protocols, third-party virtual appliances, and EC2-Classic applications. Usage charges vary by region; data transfer and public IPv4 address charges may be additional. New AWS customers receive a free tier for six months after account creation, with usage limits and up to $200 in credits.

Linux Virtual Server (LVS) turns a cluster of real Linux servers into one virtual server for users. Its IPVS component performs layer 4 balancing in the Linux kernel, directing TCP and UDP requests sent to a virtual service IP toward servers behind it. Supported forwarding methods are NAT, FULLNAT, tunneling, and direct routing. The project lists web, cache, mail, FTP, media, and VoIP services as applications. Capacity can be changed by adding or removing cluster nodes. Failure detection can identify node or daemon problems and reconfigure the system for availability. Keepalived checks server-pool state at layers 3, 4, and 5 and tells the kernel to remove a failed server. KTCPVS supplies application-level balancing but is under development. LVS is free GPL-licensed software for Linux and self-hosted use. Administration uses ipvsadm, with documentation for configurations, scheduling, high availability, and DoS defense.