mount -u -o rw / not working on NFS?

[Laszlo Nagy]

  Hi All,

I have a system where a diskless FreeBSD 6.3 i386 machine boots with pxeboot from a FreeBSD 6.3 amd64 machine. I have lines in /etc/fstab for the diskless machine like:

# Device        MountPoint      FsType  Options Dump    Pass
172.16.0.1:/usr /usr    nfs     rw      0       0
172.16.0.1:/mnt/d2/rootfs/root  /root   nfs     rw      0       0

The machine boots from network nicely, then I can login as root and invoke these commands:

mount -u -o rw /
mount -u -o rw /usr
mount -u -o rw /root

There is no error message on the console, nor in the system log. However, this happens afterwards:

diskless101#mkdir /aaa
mkdir aaa: Read-only file system

Question: if the remount did not succeed, why didn't it throw an error? If succeeded, why can't I write on the filesystem?

Thanks,

   Laszlo