Since rrdtool-1.4 uses pango for font rendering it also seems to require truetype fonts to be installed, otherwise one can see "blocks" instead of text on the graphs: [snip] Pango-WARNING **: failed to choose a font, expect ugly output. engine-type='PangoRenderFc', script='latin [/snip] It seems to search fonts from /usr/share/fonts directory (which does not exist, unless some fonts are installed).
ewarn "Note: rrdtool-1.3.x doesn't have any default font bundled. Thus if you've" ewarn "upgraded from rrdtool-1.2.x and don't have any font installed to make" ewarn "lables visible, please, install some font, e.g. media-fonts/dejavu." Dupe of Bug 280271
*** This bug has been marked as a duplicate of bug 280271 ***