改變開機時GRUB的default

我的11.04是跟windows一起裝的, 開機時會先跑ubuntu的Grub(奇怪, windows的開機選單好像被幹掉了...)

grub的開機default當然是ubuntu, 這樣對有時window update driver後重開會跑到ubuntu(如果沒在前面顧)

參照這篇:

How-to Change Boot Order in Ubuntu 11.04

關於grub的選項都是在一個 grub.cfg file裏...
不過這個檔不能直接修改ㄝ,是要去改這個檔：/etc/default/grub

亂搞之前先做分copy...sudo cp /etc/default/grub /etc/default/grub.bak


必要時可以這樣co 回來...
sudo cp /etc/default/grub.bak /etc/default/grub


改玩得時候用 ls -A就會看到這個.bak檔

要edit這個grub:

gksu gedit /etc/default/grub

裏面有許多選項....其中:

GRUB_DEFAULT=0

就是開機時的default選項, 0代表第一行的選項....對, 他是從0開始排....

或著是改成:
GRUB_DEFAULT=saved
這樣以後就可以用:(這個我還沒試)
sudo grub-set-default 1
或
sudo grub-reboot 1
去改....


這個web說,如果再加一行:

GRUB_SAVEDEFAULT=true

那就會根據上一次的OS去開....

Edit 完 grub之後, 存好離開要跑一下:
sudo update-grub
這樣就會改到 grub.cfg了

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