nfs root filesystem

I'm trying to boot my gumstix with a nfs root filesystem.  Has anybody
tried to do this?  I can't get it working.

Here's what I'm trying:

First, I rebuilt my kernel so nfs was not a module anymore and installed
this on the flash on my gumstix.

Next, I try booting with the bootargs u-boot variable set to this:

console=ttyS0,115200n8 root=/dev/nfs ip=192.168.101.106  \
   nfsroot=192.168.101.16:/home/gumstixroot reboot=cold,hard

I also set the serverip and ipaddr variables to the correct values.

I know the nfs server works, since I can mount it on the gumstix in
someplace other than root if I boot the gumstix from flash.  I can even
use pivot_root to make the nfs filesystem into the root filesystem.

Here's the last few lines of the console:

IP: routing cache hash table of 512 buckets, 4Kbytes
TCP established hash table entries: 4096 (order: 3, 32768 bytes)
TCP bind hash table entries: 4096 (order: 2, 16384 bytes)
TCP: Hash tables configured (established 4096 bind 4096)
Kernel panic - not syncing: VFS: Unable to mount root fs on
unknown-block(0,255)

Does anybody have any suggestions?

 -john.





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