[gentoo-user] System hangs when poweroff with NFS mounted

[Amankwah]

Hi all,
    I swithed to Gnome3 last week, and the systemd is needed by
gnome3.8, so I used systemd to replace the openrc now. Howerver, my
system always hangs when I try to poweroff.
    I have NFSv3 filesystem mounted via WiFi, it's managed by the
Networkmanager. so it seemed that the wireless connection was cut off
before the NFS was unmounted? I searched this problem and modified my
fstab line like this:

    NAS:/data    /media/NAS  nfs
    _netdev,x-systemd.automount,x-systemd.device-timeout=10ms,rw,soft,vers=3
    0   0

It's worked under the wired connnection, but the wireless connection
still hangs, Is there any thing should be changed? Or is it a bug?
    
I have to umount the NFS before poweroff everytime. Please tell me what can I do to
resove this problem?

Thx