Re: hd sleep mode
From: Damion de Soto (damion_at_cyberguard.com.au)
Date: Mon, 26 Sep 2005 11:45:09 +1000
> Is there anyway to get a hd out of sleep mode after putting it into
> that without a warm reboot?
> We have an embedded system that runs in cold tempertures, when the hard
> disk gets too cold, we put the hd into sleep and run out of CF, but
> when the temperture warms up, we want to get the hd back to usage
> without a reboot. Possible?
Is there any reason you can't use Standby mode instead of Sleep mode?
The disk still spins down, and you wouldn't have the trouble
of having to issue a reset to get it back online.
However, I've just re-read the hdparm man page, and it seems to be
different to last time I used standby/sleep mode:
-Y Force an IDE drive to immediately enter the lowest power consumption
sleep mode, causing it to shut down completely. A hard or soft reset is
required before the drive can be accessed again (the Linux IDE driver will
automatically handle issuing a reset if/when needed). The current power mode
status can be checked using the -C flag.
The part in brackets seems to imply the kernel can issue the reset and get the drive
Perhaps this is a new feature you should investigate..
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