Hi all, I was encountering the same issue on a slave NIS machine.
Adding the hostname of the master in the /etc/hosts file does work around this bug. I have additionally had a look at the source code of yphelper. It seems that there is a bug in function get_canonical_hostname which can read the ai_canonname of the addrinfo structure, although it may be NULL. My understanding is that modifying the /etc/hosts file makes this field non-null, and thus avoids this bug. I have also reported this bug upstream: https://github.com/thkukuk/ypserv/issues/19 Cheers, Laurent Voisin.
