[Unionfs] problems with NFS export, v. 1.4

[Michael Creel]

Hello to everyone,

I'm adapting the ParallelKnoppix live CD to export home to the compute 
nodes via unionfs. This makes things very convenient, since a uniform 
set of files is available to all the nodes in the cluster. One the 
master node, the home dir is /UNIONFS/home/pk. This is nfs exported to 
the nodes using the following entry in /etc/exports:

/UNIONFS/home/pk 
192.168.0.0/255.255.255.0(rw,root_squash,fsid=42,async,no_subtree_check)


This works fine with a 2.6.17 kernel and unionfs 1.3. However, with a 
2.6.18 kernel and unionfs 1.4, the compute nodes can't mount the 
export, and the report the typical "reason given by server: permission 
denied" error. So I'm looking for pointers as to how to get this going 
with unionfs 1.4 (or I can switch to a 2.6.19 kernel and unionfs CVS, 
if that would help).

I can supply details, if that would help. Also, though it'a a big 
download, there are 2 iso images at 
http://pareto.uab.es/mcreel/ParallelKnoppix/download/testing/
The one with "good" in the name is the working version with unionfs 
1.3 and kernel 2.6.17, the other uses unionfs 1.4 and kernel 2.6.18.2, 
and it doesn't work.

Any help would be greatly appreciated.

Regards, Michael