Bug#429428: Solution, update /etc/idmapd.conf
The domain name on the server hadn't been configured to
match the domain name in the client. This resulted in
corrupted ownership (owner and group) for the destination
files, and the 'chown_if_root' routine failed.
A trace of where pdumpfs was failing can be obtained
by specifying '--backtrace' as a command line option,
but that parameter is undocumented. I think it needs
to be not only documented in both the man page and the help,
but it should actually be the default on any error that
causes pdumpfs to stop.