how can a setup the default keymap for console??

This link has most of the info:

http://www.debian.org/doc/manuals/users-guide/ch-ctsystem.en.html#s-ctkm http://www.debian.org/doc/manuals/debian-euro-support/ch-configure.en.html

Quick solution:

loadkeys gb

System:

dpkg-reconfigure console-data
dpkg-reconfigure locales

In Ubuntu:

<Mithrandir> just use locale-gen $locale
ko_KR.UTF-8
you could also look it up in /usr/share/i18n/SUPPORTED