Re: RAID backup

[Herman Oosthuysen <Herman@WirelessNetworksInc.com>]

Yep, a constant lowish temperature will also help a little, but I 
honestly think that in storage, a disk drive bearing will seize due to 
corrosion and lack of movement, before the electronics will fail.  You 
can prevent bearing (and capacitor) problems by starting the drive up 
every 6 months for a while though.

The effects of long term storage is experienced with military equipment, 
which frequently have to stay in storage for 40 or 50 years without ever 
really being used.  The stuff in storage has to be cycled through the 
workshops to keep them operational, which is part of the high cost of peace.

If disk drives are used for backup purposes, then I would suggest that 
they are rotated, so that they all remain in occational use, which 
should help to keep them alive.  Of course, the first thing to fail, 
would be the connector of the removable drive bay and there is nothing 
you can do about that, except to make sure that the connectors are gold 
plated to begin with.

I don't think that people have to worry too much about transportation 
vibration and shock to/from an off-site storage facility.  These things 
are quite rugged when not spinning, so if you transport them in 
styrofoam boxes and don't drop them on the floor, they should be OK.

BTW, putting a drive in storage for 40 or 50 years is not recommended 
for another reason: Obsolecense.  In 40 or 50 years, you probably won't 
have a computer that can use these drives anymore!  So, the only way to 
keep data long term, is to rotate the media continuously and upgrade as 
new technology is introduced.

Cheers,

Herman
http://www.AerospaceSoftware.com

Russell King wrote:
> On Fri, Oct 04, 2002 at 09:31:26AM -0600, Herman Oosthuysen wrote:
> 
>>Self demagnetization used to be a problem of magnetic media and some 
>>components such as capacitors used to deteriorate with age, but I think 
>>that those problems have been solved decades ago, so equipment in clean 
>>and dry storage should last almost forever.
> 
> 
> You missed "stable temperature" as well.  Some capacitors still
> "dry out" with age and heat, even with todays technology.
> 

-- 

------------------------------------------------------------------------
Herman Oosthuysen
B.Eng.(E), Member of IEEE
Wireless Networks Inc.
http://www.WirelessNetworksInc.com
E-mail: Herman@WirelessNetworksInc.com
Phone: 1.403.569-5687, Fax: 1.403.235-3964
------------------------------------------------------------------------