Populate /root/sup with supfiles copied from /usr/share/examples/cvsup
mkdir -p /root/sup cp /usr/share/examples/cvsup/ports-supfile /root/sup/ports.sup cp /usr/share/examples/cvsup/stable-supfile /root/sup/RELENG_8_0.sup
Patch the supfiles to indicate your server du jour
suptag="RELENG_8_0"
supsrv="cvsup14.FreeBSD.org"
sed -e "s/^\(\*default host=\).*$/\1${supsrv}/g" -e "s/^\(\*default release=cvs tag=\).*$/\1${suptag}/g" -i /root/sup/RELENG_8_0.sup
sed -e "s/^\(\*default host=\).*$/\1${supsrv}/g" -i /root/sup/ports.sup