> I do backups of my important files to a rewritable CD-ROM
> using mkhybrid and cdrecord, on an 1.5.2/i386.
> 
> A little script creates the image first, pulling in some local
> files and some files over NFS. I am seeing some very strange
> erratic behaviour with this:

You might (dunno) be falling over a little problem I found a couple
of years ago while making CD images from a 'union' type filesystem.

mkisofs uses the file system id and inode number returned by stat()
to identify unique files.  If these values are not setup correctly
- ie they are not unique for real files, then mkisofs will not
generate a correct image.

I've had a (very) quick look at the netbsd union fs, it doesn't do
anything to ensure these values are unique.
It is also possible that NFS gets it wrong...

    David