The main goal of the keepalived project is to add a strong & robust keepalive facility to the Linux Virtual Server project. This project is written in C with multilayer TCP/IP stack checks. Keepalived implements a framework based on three family checks : Layer3, Layer4 & Layer5/7. This framework gives the daemon the ability to check the state of an LVS server pool. When one of the servers of the LVS server pool is down, keepalived informs the linux kernel via a setsockopt call to remove this server entry from the LVS topology. In addition keepalived implements an independent VRRPv2 stack to handle director failover. So in short keepalived is a userspace daemon for LVS cluster nodes healthchecks and LVS directors failover.