am-utils/NFS mount lockups in 8.0

[Rick Macklem]

On Sat, 19 Dec 2009, Bob Friesenhahn wrote:

> After upgrading my FreeBSD system from FreeBSD 7.2 to 8.0, the am-utils 
> automounter is experiencing difficulty with managing the NFS client mounts to 
> my Solaris 10U8 system.  There have never been any difficulties before.  This 
> is when using the NFSv3/TCP in the default kernel and not the new NFSv4 
> implementation.  If it matters, this is for NFS exports from a ZFS pool, with 
> an exported filesystem per user.
>
> The problem I see is that the initial mount is instantaneous and works great. 
> After the mount times out, the re-mount produces several "NFS timeout" 
> messages to the widow where the accessing program is running. Sometimes this 
> remount succeeds, but if it fails, then the program is left locked up forever 
> waiting for the NFS mount.  Meanwhile connectivity between the FreeBSD system 
> and the Solaris system is fine, as illustrated by excellent connectivity with 
> SSH and no lost packets via 'ping'.
>
You could try the patch at:
http://people.freebsd.org/~rmacklem/patches/freebsd8-clntvc.patch
(Fixes an issue w.r.t. client side TCP reconnects and didn't quite make
it into 8.0.)

I am trying to keep a list of FreeBSD8.0 NFS fixes at:
http://people.freebsd.org/~rmacklem

Good luck with it, rick