Ubuntu error : /etc/default/console-setup: /: Permission denied

error msg> 

Setting up initramfs-tools (0.122ubuntu8.10) ...
update-initramfs: deferring update (trigger activated)
Processing triggers for initramfs-tools (0.122ubuntu8.10) ...
update-initramfs: Generating /boot/initrd.img-4.13.0-32-generic
/usr/share/initramfs-tools/hooks/console_setup: 11: /etc/default/console-setup: /: Permission denied
E: /usr/share/initramfs-tools/hooks/console_setup failed with return 126.
update-initramfs: failed for /boot/initrd.img-4.13.0-32-generic with 126.
dpkg: error processing package initramfs-tools (--configure):
 subprocess installed post-installation script returned error exit status 126
Errors were encountered while processing:
 initramfs-tools
E: Sub-process /usr/bin/dpkg returned an error code (1)

우분투 apt-get 등 모든 initramfs-tools가 이렇게 에러가 날때.. 

원인은 

/etc/defaults/consoloe-setup 파일의 

ACTIVE_CONSOLES="/dev/tty[1-6]"

CHARMAP="UTF-8"
CODESET="guess"

FONTFACE="Terminus"
FONTSIZE="24x12" / "24"


해당 폰트 사이즈 부분.. 왜 이렇게 설정된건지 모르겠지만. 

이것을 직접 FONTSIZE="24x12"  이렇게 고쳐도 되고.. 
직접 고쳐도 되는지 못 미더울때는 

>> sudo dpkg-reconfigure console-setup 

이것으로 설정해줘도 된다..