I am trying to boot a server using a root partition on NFS. There are many web hits on this topic, but none seem very recent. The problem is that the last thing that comes out on the console is

nfsmount: error mounting /dev/nfs on /sysroot as nfs: No such file or directory

But a few more details on just what it can not find (host, file, ..) woluld be helpful. I could not find a kernel param that offered more logging (debug does not help here).

What I did was
1) add nfs support to the kernel ( CONFIG_NFS_FS=y ... ) and put it in /boot
2) make the root an nfs mount in /etc/fstab (on the nfs root)
3) mkinitrd --fstab=<the above file> for a new initrd... in /boot, and this seems to have done the right stuff (i.e. looking into the init script).
4) put an entry into /boot/grub/menu.lst that says
kernel /vmlinuz-2.6.27.20_nfs.x86_64 ro root=/dev/nfs nfsroot=10.3.1.222:/perf_linux_share/diskless_roots/poc06 rhgb quiet

The share 10.3.1.222:/perf_linux_share/diskless_roots/poc06 does in fact exist, thout /perf_inux_share is what is exported not the sub-directory, is that ok? (I am not restricting sub-dir mounts). If I just cut and past the nfsroot= arg into a mount, it works fine.

I tired adding all the ip= (aka nfsaddr=) stuff but that did not help. I get the same error even if the target root on nfs is in fact missing (i.e. renamed) so I'm guessing it can not find it, but I don't see why.

Anyone know how to get more info on what is going wrong?
-jrg