no package samba-winbind-krb5-locator available

I am attempting to add AD authentication to my server and am following the instructions from the Red Hat Enterprise Linux 7.4 Windows integration guide. In section 4.3.2 step 3 says to install package samba-winbind-krb5-locator using yum. Yum responds with the error "no package samba-winbind-krb5-locator available". What repository needs to be enabled to find this package.

Thanks,

Dave