/usr/share/texmf-texlive/dvips/tetex/config.dfaxlo is in texlive-base 2009-15.
This file is owned by root:root, with mode 0o644.
The actual contents of the file can be viewed below.
1 2 3 4 5 6 7 8 9 | % Thomas Esser, 1998, public domain.
% Usage: dvips -Pdfaxlo ...
% Purpose: set up dvips' resolution to be optimal for a G3 fax at low
% resolution (204x98)
M gtfaxlo
X 204
Y 98
|