grub2 配置命令备忘

之前装Windows把grub搞挂了，用ubuntu 9.10的盘不能恢复，才发现grub2时代已经来了

又搞了个ubuntu 9.04的盘恢复以后，索性就升级到了grub2。当时有很多问题，尤其是分辨率那个。现在装了10.04，似乎没什么问题了，常用配置命令整理如下

旧版升级：
sudo upgrade-from-grub-legacy

去掉memtest:
sudo chmod -x /etc/grub.d/20_memtest86+

修改背景图片/颜色:
sudo vim /etc/grub.d/05_debian_theme 注意背景black表示透明，否则会挡住背景图片

修改控制台分辨率：
sudo vi /etc/grub.d/00_header 在 set gfxmode=${GRUB_GFXMODE} 后加入 set gfxpayload=keep
注意同时要修改/etc/default/grub里面的 GRUB_GFXMODE

其他参数：
修改 /etc/default/grub，里面的注释写的很清楚的

更新grub菜单，重新搜索内核等等
sudo update-grub
这个很不错，一个是能自动搜索windows loader，另一个就是再也不用为“是(hd0,4)还是(hd0,5)”之类的问题发愁了

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