My beef with NAC is that the tech guy said that there had been many problems like this, alot of open tickets in the support queue and that the next release of the OS would have the tcp option disabled (as the default; not removed).
Why in the world has NAC not sent out an advisory about this? If it has been causing so many problems, the least they could have done is let us know that it could happen.
Since this is a new filer (f540, 256MB read cache, 8MB nvram, 100GB, 2x100bT, 1 fddi), the problem only affected some setup stuff I was doing. The problem seems worse with fddi than with ethernet connections (my mounts that occured over ethernet were fine while the fddi ones were not).
Anybody from the peanut gallery?
It is interesting to note that many other vendors have problems with their NFS/TCP implementations as well... generally in the area of performance, but stability as well.
Also note that your subject line is somewhat misleading... NFS version 3 and NFS over TCP are completely orthogonal, and one can run NFS v2 over TCP or NFS v3 over UDP. The only thing they have in common is that most vendors started supporting both at roughly the same time.
I'm not involved with the support policies but obviously the scope of the problem plays into any decision to make an announcement. If there is a critical bug that surfaces, but it's unlikely that many customers will encounter it, should an announcement go out? I have mixed feelings about the answer, and in any case my opinion doesn't matter... yours does. So, as customers, it is important that you provide feedback to Network Appliance on this very point, so Customer Service can service you better.
Bugs On-Line (a benefit of NOW) is a good source of data on bugs that are not announced through field alerts. (BTW, I see bug #3800 listed there, which mentions the ethernet interface could also hang with NFS/TCP traffic.)
Bruce
PS - I know many of you are fond of the name, but it would also be politically correct to point out that we are no longer NAC! We changed our name to Network Appliance, Inc. about the time we went public. Although if you have rows of filers all named nac1, nac2, nac3, etc., changing them all would probably be a pain. :)