HAProxy Community Edition vs Linux Virtual Server

HAProxy Community Edition is free, self-hosted software for proxying TCP and HTTP applications, with high availability and load balancing. It is aimed especially at very high-traffic websites. HAProxy runs on Linux, where it is included with most mainstream distributions and is often deployed by default on cloud platforms. Its event-driven design uses light multithreading on SMP machines. The project lists Layer 4 and Layer 7 routing and TLS termination, along with TCP and HTTP support; recent versions also include QUIC and HTTP/3 features. Listed safeguards include chroot, privilege drops, fork prevention, strict protocol validation, and checks for impossible states. The site reports up to 2 million SSL requests per second and 100 Gbps of forwarded traffic on AWS Graviton2. HAProxy 3.4 is in development, and 3.4.6 is the latest listed release in that branch. Its features include dynamic backends, HTTP/2 flood protections, ACME improvements, experimental QMUX, and an OpenTelemetry filter. LTS branches receive five years of maintenance; other stable branches receive 12 to 18 months.

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.