Zombie NFS writing from FreeBSD clients to FreeBSD 8.0 server with ZFS

[Rick Macklem]

On Wed, 6 Jan 2010, alan bryan wrote:

> I have a AMD64 FreeBSD 8.0 server with ZFS filesystem being shared via NFS.  These are being accessed by the clients.  The clients are a mix of FreeBSD 6.2 32bit and FreeBSD 7.0 64bit.  I have seen similar behavior from both versions of FreeBSD as clients.
>
[stuff related to lotsa writes being done snipped]
>
> Any ideas on what to try, where to look for more insight, etc...??
>
It might be worth taking a look at the traffic. Wireshark (or a tcpdump
packet capture read into wireshark) does a good job of interpreting NFS
traffic. "tcpdump -s 0 -w <file> host <client>" run for a
short period of time when <client> has the problem and then looking at
that in wireshark would at least allow you to see what the writes
look like?
- Are they the same write being retried over and over?
- Is the server replying to them with an error?

The above might give some insight into what's happening, rick