If you’re using Raspberry Pi, you might know the famous command line utility
dd, useful to write a Raspbian image to a blank SD card (cf. http://elinux.org/RPi_Easy_SD_Card_Setup).
You can also use this tool to do backup of the whole disk, but it has two drawbacks :
- when you copy the whole disk, the image is as big as the disk, even if the is lots of empty space on it.
- when you restore the backup you need a disk at least as big as the original one.
Those two disadvantages lead me to find a solution to make backups smaller and more versatile. The solution I’ll describe here is an adaptation of Ubuntu’s documentation : https://help.ubuntu.com/community/BackupYourSystem/TAR and have been tested on Ubutnu 14.04.
Here are few modification that allow a very quiet boot, nothing will appear on the screen before the login prompt.
Thus if you start a visual application before that (in /etc/init.d for example) you will not see anything on the screen before your application starts.
First modify the /boot/cmdline.txt like this :
dwc_otg.lpm_enable=0 console=ttyAMA0,115200 kgdboc=ttyAMA0,115200 console=tty3 root=/dev/mmcblk0p2 rootfstype=ext4 elevator=noop rootwait loglevel=3 logo.nologo vt.global_cursor_default=0
here are the details of the changes :
console=tty3 redirect all the post messages to the third console (hit CTRL + ALT + 3 to see them after boot).
loglevel=3 make it less verbose, only errors are reported
logo.nologo disable the RaspberryPi logo on boot
vt.global_cursor_default=0 Disable the blinking cursor.
Moreover you can add
disable_splash=1 to /boot/config.txt in order to disable the rainbow splash on power on.
At the en, vous can completly disable the prompt #1 by editing the file
/etc/inittab and commenting the following line :
1:2345:respawn:/sbin/getty --noclear 38400 tty1
That’s all !