Wiley Press, ISBN 0-471-43026-9, Even Marcus & Hal Stern

Whatever you do, don't read this book when planning your enterprise-class 
PostgreSQL cluster using Slony1.  The author(s) give a scathing opinion of 
network based asynchronous database replication.  Especially for redundant 
configurations within the same facility.  They concede that the method has 
some applicable uses (facility to facility replication), but they go so 
far as to recommend long distance SAN before software+network.

The entire text has a highly anti-microsoft undercurrent which makes it a 
real page-turner, unfortunately, most of the advice regarding HA 
application clusters has a commercial-UNIX oriented slant (they all but 
endorse VERITAS).

The book only serves to further emphasize that there is no definitive FMS 
(Fail over Management Software) solution for Open Source UNIX-like OSs. 
No true platform-independent (well, Linux-HA[.org]) project that 
integrates with monitoring, databases, web servers, load balancers, RAID 
/ SAN controller, etc.

The projects are there (PostgreSQL, Slony, PGPool, Nagios, Net-SNMP, 
FreeVRRPd, FreeBSD, GNU/Linux, Linux-HA, etc..), there just no integration 
yet.

~BAS