is NFS production-ready ?

[dima]

First, searching through the archives I'm about to say "No".

My goal is to provide NFS service to many FreeBSD clients sharing the exports. The usage pattern appears to be "many reads and not as much writes".
The deployment might look like the following: a SAN and 2 NFS servers sharing its LUNs. The servers use hot-standby scheme provided by CARP (or its equivalent). Many FreeBSD clients would share their exports. I wish servers ran FreeBSD also since it's the best known OS for the company administrators.

The majors are:
- no data corruption
- no hangs (this seems to be the largest problem with current implementation)
- client retry on failure
- a reasonable read speed

My questions:
1. NFS/UDP (it's stateless!) is considered to be "evil". Why (assuming I can grant a balanced network bandwidth)?
2. NFS server implementation seems to be very buggy. Any success stories? Well, NFS servers can easily run Linux, Solaris etc.
3. Is at least implementation of NFS client (either kernel-side or user-space) stable enough for production use? Client OS replacement is impossible (hardly suitable, really) in my project.

PS: The competing options are either SMB or CODA for now. Any other suggestions?

PPS: I'd be happy to hear that FreeBSD supports at least one really clustered FS (proprietary ones are also OK). But I think I wouldn't :(