Forcing ethernet duplex and speed during startup on linux (Suse)

a) Modify /etc/sysconfig/network/config file to have
  following options set to 'yes'.

GLOBAL_POST_UP_EXEC="yes"
GLOBAL_PRE_DOWN_EXEC="yes"

b) Create a script file (E.g, ethtool-settings) in
  /etc/sysconfig/network/if-up.d directory with required ethtool commands.

E.g, the file can contain the following ethtool command -

  /usr/sbin/ethtool -s ethX speed 10

c) Set the mode of the file to 755.
#chmod +755 ethtool-settings