Boot the Router over Network TFTP+NFS

[tomekmik]

I have try to boot my new wl500gx over the Network but it doesn't work.
What have i do:
1.Make a new kernel with NFS Client support and place the file vmlinux_nfs to TFTP Sever
2.Set the kernel arguments:
CFE> nvram set kernel_args "root=/dev/nfs nfsroot=192.168.1.6:/nfs_rootfs noinitrd init=/linuxrc console=ttyS0,115200"
CFE> nvram commit
I'm not sure it is valid for this kernel???
3. Boot over TFTP Server
CFE> boot -elf -tftp 192.168.1.6:vmlinux_nfs

The Router load the kernel and the kernel panic :
VFS: Cannot open root device "nfs" or 00:ff
Please append a correct "root=" boot option
Kernel panic: VFS: Unable to mount root fs on 00:ff


I think that the kernel_args are wrong or my kernel have not the right device /dev/nfs for mount the nfs rootfs.But i don't now how to fix it?
Have somebody try this on a Asus Router?
Hope somebody can help me.
Tomek