Read the docs from MRTG :). Learn to use MRTG :).
Change "ADMINDIR" in the Makefile to where you want to put the
executable and the tables.
Change "$SNMPGet", "$TableBase" and "$Community" in GetSNMPLinesUP.pl
for your correct values.
See sample.cfg for a sample configuration entry of a machine with some
modems connected.
See ModemTable.dial-machine for the corresponding variables to check
in this sample.