High availibility: vrrpd, usage, configuration and security

This document is about about high availability and more especially about vrrpd(http://w3.arobas.net/~jetienne/vrrpd), an implementation of VRRPv2 as specified in rfc2338. It runs in userspace for linux. In short, VRRP is a protocol which elects a master server on a LAN. If the master fails, a backup server takes over.

The paper will present vrrpd in 3 parts: (i) the protocol vrrp: its specificities and limitation, (ii) the implementation of vrrpd: how it works on linux, what have been and still are the problems, what are the security problem and how they have been solved, (iii) the configuration of vrrpd: several example of configuration, basic one and more complex ones (e.g. port tracking).