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

Rick Macklem rmacklem at uoguelph.ca
Wed Jan 6 20:48:11 UTC 2010



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.
>
> The behavior that I'm seeing is that everything is fine for a period of time and then the client starts "writing" large amounts of data to the NFS server.  "Writing" is in quotes as nothing is actually being written to disk - this can go on for 12+ hrs or more - until the client is rebooted. It appears to cap out at around the 10-20Mbps rate and just sit there.  Other clients are fine during this time.
>
>
> Client mounts in /etc/fstab look like:
> 192.168.1.33:/tank/share /usr/local/www/share nfs rw,-b,-i,-U,-3 0 0
>

One other thing you could try is switching to TCP mounts (replace -U
with -T). There are a couple of others that have reported NFS server
problems (all different symptoms) where the problem went away when
they switched to TCP.

rick



More information about the freebsd-stable mailing list