Messages in this thread | | | Date | Wed, 6 Jan 1999 00:02:00 -0800 (PST) | From | George Bonser <> | Subject | Re: Rescan IDE interfaces |
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On Tue, 5 Jan 1999, Mike A. Harris wrote:
> Just for the record (I know this is a reply to an old posting, > but...) I've hotswapped a few IDE drives and have had no problems > at all. a call to hdparm to spin the drive down, then unplugged > it and it worked fine.
You got lucky. One of the problems with most IDE drives is that unless the connector is designed for hot swapping, there is no guarantee which pins will make/break contact first. It is possible, in some cases, to damage hardware because contact is made in the wrong order. If data signals are present before the main power or if there are (as there usually are) several different supply voltages (usualy two positive voltages and one negative), the order that they are applied can be important. Connectors designed for hot-swap have pins of differing lengths so that the circuits are broken/restored in a known order.
Plan the downtime and swap the drive/cable. What you risk is damage to the controller and all drives on the bus. It might work 49 out of 50 times but that one time will kick your ass and it might happen the first time you try it or the 50th. I know a guy that used to hot-swap drives too. He doesn't anymore. Planned downtime is always a LOT better than unplanned.
George Bonser
From our family to you, a toast. Peace, Health, and Prosperity.
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