Hi, If you're basically building a high-volume web farm then don't reinvent the wheel and use standard deployment architectures. Having the content on a NFS server behind the web servers is an attractive and potentially low cost route, even gigabit networking is relatively affordable these days. If fully shared storage is *truly* what you need then NFS is the easiest option. Also, think about the likely data access patterns. Do you have large amounts of static content? If so then this could be local on each server, leaving only the truly dynamic content requiring the shared storage. That likely allows you to get away with a less beefy NFS server and back-end network. I'd also ask you to take a very long hard look at the stated requirement for instantaneous synchronisation across the multiple servers. Building a highly available web service is exceptionally difficult if the requirement list includes phrases such as instantaneous, "fully transparent" and "no single points of failure". What you really need to understand is the implication of the possible failure scenarios and just what impact that will have on the service clients. Often when cost and complexity are taken into account the requirements soften somewhat. Otherwise you end up designing systems where you want to have users in pairs in case one spontaneously combusts. You can push points of failure further up and downstream but at some point you have to accept some risk. Regards, Garry Garry Turkington garry.turkington at acm.org
