/usr/lib/aolserver4/bin/nsd is in aolserver4-daemon 4.5.1-18.
This file is owned by root:root, with mode 0o777.
It is a symlink to /usr/lib/aolserver4/bin/../../../sbin/aolserver4-nsd
/usr/lib/aolserver4/bin/../../../sbin/aolserver4-nsd