ypwhich [ -t mapname ] [ -d domain ] -m mname
ypwhich -x
Refer to ypfiles(NF) and ypserv(NADM) for an overview of the Network Information Service.
If the version is not specified, ypwhich attempts to locate the server that supplies the (current) v.2 services. If there is no v.2 server currently bound, ypwhich then attempts to locate the server supplying the v.1 services. Since NIS servers and NIS clients are both backward compatible, the user need seldom be concerned about which version is currently in use.