(Semi)hot swap IDE

Jez Hancock jez.hancock at munk.nu
Sun Nov 23 15:57:26 PST 2003

On Sun, Nov 23, 2003 at 01:16:50PM +0200, Toomas Aas wrote:
> > 1.  The 'generic' removeable drive trays for IDE that use a normal IDE 
> > controller (like attaching to the slave or secondary channel on most 
> > onboard IDE), with another disk or device attached that's being used, do 
> > not support removeable devices.  It's _extremely_ likely that you'll 
> > hang the IDE bus.
> If there is only CD-ROM (which is almost never used) attached as 
> primary master and the removable disk attached as secondary master then 
> maybe I don't need to worry too much about that.

Just for the record I have the kind of setup you're talking
about - I successfully 'hot swapped' a 40Gb IDE disk using a hdd
caddy tray but there are caveats (mostly highlighted above) - using the
term 'hot swap' loosely here because it just doesn't feel too clever
doing it :P

I found the following:

- I could remove/reinsert the device only if it was originally in the machine on
  boot - this is fairly obvious I suppose.  Otherwise the device just
  doesn't show up.

- I could re-insert the device successfully but only if I'd umounted it
  first before removing it.

- Removing the disk without umounting produced random results -
  sometimes the disk could be re-inserted ok, other times not, as the
  previous poster mentioned the IDE controller appears to hang.

For the record iirc the disk was attached to the secondary ide
controller with a hdd and a cdrom drive on the first ide controller.

Best thing is to play - doesn't make as much noise (or smoke) as
hot-swapping PCI cards!

Jez Hancock
 - System Administrator / PHP Developer


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