Package: yp-tools

"yp-tools" package binaries on CentOS:

/usr/bin/ypcat /usr/bin/ypchfn /usr/bin/ypchsh /usr/bin/ypmatch /usr/bin/yppasswd /usr/bin/ypwhich /usr/sbin/yppoll /usr/sbin/ypserv_test /usr/sbin/ypset /usr/sbin/yptest

You may install this package on CentOS with yum install yp-tools