My server SLES12Sp1 is working quite well but I have troubles with X11 clients since
they (eg xterm) only have six fonts available.

xlsfonts returns only the following six fonts (and only them can be used by xterm):

-misc-fixed-medium-r-semicondensed--0-0-75-75-c-0-iso8859-1
-misc-fixed-medium-r-semicondensed--13-100-100-100-c-60-iso8859-1
-misc-fixed-medium-r-semicondensed--13-120-75-75-c-60-iso8859-1
6x13
cursor
fixed

But I have a lots of installed fonts on my server!
fc-list|wc
1948 7460 152082

I read around that X11 fonts are different from "now standard" fonts, but I don't know how to give X11 the fonts listed by fc-list
I hoped it was fonts-config but it doesn't work:

fonts-config -v
Creating fonts.{scale,dir} files .........................
Creating cache files for fontconfig ..........................................
Creating 32bit cache files for fontconfig ..........................................
It is not a local display, do not reread X font databases for now
Generating java font setup ...
warning: cannot find a Japanese sans serif font, Japanese might not work in Java
warning: cannot find a Japanese monospace font, Japanese might not work in Java
warning: cannot find a Japanese serif font, Japanese might not work in Java
warning: cannot find a Simplified Chinese sans font, Simplified Chinese might not work in Java
warning: cannot find a Simplified Chinese serif font, Simplified Chinese might not work in Java
warning: cannot find a Traditional Chinese sans font, Traditional Chinese might not work in Java
warning: cannot find a Traditional Chinese serif font, Traditional Chinese might not work in Java
warning: cannot find a Korean sans font, Korean might not work in Java
warning: cannot find a Korean serif font, Korean might not work in Java

xlsfonts
-misc-fixed-medium-r-semicondensed--0-0-75-75-c-0-iso8859-1
-misc-fixed-medium-r-semicondensed--13-100-100-100-c-60-iso8859-1
-misc-fixed-medium-r-semicondensed--13-120-75-75-c-60-iso8859-1
6x13
cursor
fixed

Any help will be very apreciated,
ciao,
Emanuele

This is the list of X11 related installed rpm:
rpm -qa | grep -i x11 | sort
dbus-1-x11-1.8.16-19.1.x86_64
emacs-x11-24.3-16.32.x86_64
ghostscript-x11-9.15-6.5.x86_64
libQt5X11Extras5-5.5.1-3.2.x86_64
libX11-6-1.6.2-4.12.x86_64
libX11-6-32bit-1.6.2-4.12.x86_64
libX11-data-1.6.2-4.12.noarch
libX11-devel-1.6.2-4.12.x86_64
libX11-xcb1-1.6.2-4.12.x86_64
libX11-xcb1-32bit-1.6.2-4.12.x86_64
libqt4-x11-32bit-4.8.6-7.1.x86_64
libqt4-x11-4.8.6-7.1.x86_64
libxkbcommon-x11-0-0.4.1-3.1.x86_64
patterns-sles-x11-12-64.3.x86_64
perl-X11-Protocol-0.56-12.19.x86_64
pulseaudio-module-x11-5.0-2.7.x86_64
x11-tools-0.1-205.1.noarch
x11perf-1.5.4-1.15.x86_64
xorg-x11-7.6_1-14.17.noarch
xorg-x11-Xvnc-1.4.3-14.1.x86_64
xorg-x11-devel-7.6-45.14.noarch
xorg-x11-driver-input-7.6_1-11.10.noarch
xorg-x11-driver-video-7.6_1-14.30.x86_64
xorg-x11-essentials-7.6_1-14.17.noarch
xorg-x11-fonts-7.6-29.45.noarch
xorg-x11-fonts-core-7.6-29.45.noarch
xorg-x11-libXpm-7.4-1.17.x86_64
xorg-x11-libs-7.6-45.14.noarch
xorg-x11-libxcb-7.4-1.29.1.x86_64
xorg-x11-proto-devel-7.6-49.97.x86_64
xorg-x11-server-7.6_1.15.2-51.2.x86_64
xorg-x11-server-extra-7.6_1.15.2-51.2.x86_64
xorg-x11-server-sdk-7.6_1.15.2-51.2.x86_64
xorg-x11-util-devel-7.6_1-7.15.noarch
yast2-x11-3.1.3-2.14.x86_64