"shutdown -r now" crashed after overclocking

Question

How I hosed my ext4 file system in the first hour with Raspbian:

I have always used shutdown -r now. I tried this after editing my overclocking parameters manually. I remember setting arm_freq to 900 and sdram_freq to something (!), carefully of course. I followed with

shutdown -r now

The screen froze, no response from keyboard or mouse. A power off was the only option. On restart I've got ext4 errors and eventually I decided it required a re-image. I notice a lot of people use:

halt or reboot

but I still assume shutdown is fine. Do you have any ideas on what could go wrong?

UPDATE: This happened with a Maplin build of Raspbian. With the latest downloaded build, could not reproduce this.

Answer 1

shutdown, halt and reboot should all safely close you system before turning it of (or rebooting). So it's definitely not the cause of your problem. So it's either because of overclocking or some other error you did when trying this.

We can't check that since you already overwritten the card contents. Next time you have similar problem, you can first investigate the /boot/ partition content using SD card reader on other computer and try to recover config.txt from backup or remove it to get default values. This way you can be sure that it was not the issue with wrong config.txt options. You can also use jumper to run emergency mode (see my answer to this question).