Strange case of vanishing disk

Wojciech Puchar wojtek at
Mon Jun 4 17:26:40 UTC 2012

> I just "offlined" the system and took a look at the BIOS. The hard disk 
> controller was set to "ATA NATIVE", I attempted changing to AHCI and the 
> system failed to boot thereafter.

do you have ahci and ada drivers compiled in?

> Booting into my rescue CD of FreeSBIE, with AHCI enabled only showed "ad4" 
> (the troubled disk) to be registering.

showing up some, but not all disks after rebooting is quite common to the 
problem i described.

POWERING OFF (by disconnecting electricity, not by power button), waiting 
a minute, and powering on "fixes" the problem for some time.

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