Linux Virtual Server vs OpenELB

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.

OpenELB exposes Kubernetes LoadBalancer services externally in bare-metal, edge, and virtualization environments. It assigns service addresses from Eip-managed IP pools and supports BGP, Layer 2, and VIP load-balancing modes. BGP mode uses GoBGP to publish routes to peer routers and supports ECMP, while BgpConf and BgpPeer custom resources configure BGP properties. Layer 2 mode requires infrastructure that permits anonymous ARP/NDP packets. VIP mode uses VRRP for high availability. OpenELB can be installed with kubectl manifests or Helm 3 in Kubernetes 1.15 or later, and guides are listed for Kubernetes, K3s, and KubeSphere. The project currently supports IPv4 only and is not a managed service. Layer 2 and VIP modes forward through one active node, so failover can briefly interrupt services and bandwidth is limited by that node. BGP requires a router supporting BGP and ECMP. OpenELB uses Apache License 2.0.