Month: December 2008

  • How to define shorewall rules to allow VRRP traffic

    It is essential for routers that implement the Virtual Router Redundancy Protocol to be able to communicate with each other. As the protocol defines, the master router needs to send multicast packets to the whole subnet and of course, the rest of the backup routers need to receive this announcements otherwise they will think that […]

  • KeepAlived Installation under Debian Etch

    Briefly, KeepAlived is a daemon that is able to provide failover capabilities to servers/services by binding virtual IP addresses to machines. In the event of failure, KeepAlived would reassign this virtual IP to another machine. This action is executed fast (less than 2 seconds) and automatically. This is a very interesting daemon to be used […]

  • Having HAProxy check mysql status through a xinetd script

    HAProxy is able to load balance MySQL wonderfully. The main issue is how to make sure that the backend MySQL server to forward the request to is up and running (I mean not just to establish a connection to port 3306, I mean something more “complete”, that performs a little operation against the MySQL server). […]