freevrrpd is a VRRP (Virtual Router Redundancy Protocol) implementation
daemon under FreeBSD, NetBSD and OpenBSD.
This daemon has been rewritten from scratch and is not based on
existing projects.  In this second public release, you can find:

       * A daemon RFC 2338 Compliant adapted on FreeBSD systems
       * Implementation of Virtual Adresses
       * Support for multiples VRID
       * Master announce state by sending multicast packets via BPF
       * Changing routes and IP in 3 seconds
       * Doing gratuitous ARP requests to clean the cache of all hosts
       * Election between different slave servers
       * Same host can be Slave and Master at the same time
       * Automatic Downgrade to Slave if a Master is up again
       * Anti-Address Conflict system
       * Multi-threaded vrrp daemon
       * Plain text password authentication
       * Using now only one BPF device for all VRID
       * Support netmask for Virtual IP addresses
       * Support for monitored circuit and dependances between VRIDs
       * Support for VLAN pseudo devices under *BSD

WWW: http://www.b0l.org/?idcategory=3&idsection=1