Problems unmounting/fssyncking extern UFS filesystem

Oliver Fromme olli at lurza.secnetix.de
Wed Nov 29 08:07:17 PST 2006


Christopher Sean Hilton wrote:
 > Kevin Oberman wrote:
 > [ ... ]
 > > The magic phrase is "buffer cache has been flushed". In the real world
 > > of discs with cache there is no way to be certain when the data is
 > > REALLY on the disc. That is why things get clobbered if the power is
 > > cycled to the disc too soon after syncing and why a sleep (or typing
 > > sync three times) is still a good idea and probably always will be.
 > 
 > Please understand that this is an honest question but isn't that true
 > only of IDE heritage drives. E.g. If a SCSI drive with Tagged Queuing
 > says that the the bits have been written doesn't it mean that the bits
 > have really been written?

Right, unless the SCSI drive has a label saying "Quantum".

Best regards
   Oliver

PS:  Quantum is today owned by maxtor, isn't it?  I've lost
track of HD manufacturers when Seagate bought Conner ...

-- 
Oliver Fromme,  secnetix GmbH & Co. KG, Marktplatz 29, 85567 Grafing
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