2010年1月16日 星期六

grub rescue after re-partition by Windows

Situation:
I install Ubuntu9.10 (with grub loader) in /dev/sda10.
(My MBR bootloader is spfdisk)
Someday, I boot the system to Windows (/dev/sda2) and re-partition /dev/sda3 to NTFS.
After rebooting to Ubuntu9.10, a problem comes: some Windows program has changed the disk MBR and my Ubuntu9.10 is no more in /dev/sda10. It's in /dev/sda9 in the new MBR.

So when boot to /dev/sda9, grub can't find linux in /dev/sda10.
It is in /dev/sda9 now !



--------- in grub rescure, manually boot to /dev/sda9 -------

grub rescue>

set prefix=(hd0,9)/boot/grub

insmod (hd0,9)/boot/grub/linux.mod

----- now you can use [tab] auto-completion ---

set root=(hd0,9) linux /boot/vmlinuz26 root=/dev/sda9 initrd /boot/kernel26.img boot

----- this will boot to Ubuntu 9.10 ------

sudo update-grub
sudo grub-install /dev/sda9

(this will update your grub settings, esp. your boot menu,
so that you can boot normally into Ubuntu9.10 next time)


Reference:

2010年1月13日 星期三

generate a (pseudo) random number in sh

Print a pseudo-random byte (hex) in sh:

cat /dev/urandom | od -t x1 -A n -N 1

->89

-----------

Create a pseudo-random file of size 1 MB:
dd if=/dev/urandom of=a.log bs=1M count=1


Ref:

2010年1月1日 星期五

Install a New font in Ubuntu

For instance, I want to install a new font "Crisp" to my Ubuntu 9.10:


1. Create a new directory for your new font:

sudo mkdir /usr/share/fonts/truetype/crisp/

sudo cp ~/download/Crisp.ttf /usr/share/fonts/truetype/crisp/


2. Rebuild the font information files:

sudo fc-cache -f -v | grep -i crisp

-> /usr/share/fonts/truetype/crisp: caching, new cache contents: 1 fonts, 0 dirs


3. Restart the programs in which you want to use the new font.


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Ref: