Journaling no protection against power drop
Journaling no protection against power drop
Posted Sep 10, 2009 20:58 UTC (Thu) by Cato (guest, #7643)In reply to: Journaling no protection against power drop by anton
Parent article: Ext3 and RAID: silent data killers?
UPSs are useful at least to regulate the voltage and cover against momentary power cuts, which are very frequent where I live, and far more frequent than UPS failures in my experience.
Posted Sep 10, 2009 21:34 UTC (Thu)
by anton (subscriber, #25547)
[Link]
It depends on where you live. Here power outages are quite
infrequent, but mostly take so long that the UPS will run out of
power. So then the UPS only gives the opportunity for a clean
shutdown (and that opportunity was never realized by our sysadmin when
we had UPSs), and that is unnecessary if you have all of the
following: decent drives that complete the last sector on power
failure; a good file system; and a setup that gives the file system
what it needs to stay consistent (e.g., barriers or hdparm -W0). And
of course we have backups around if the worst comes to worst. And
while we don't have the ultimate trust in ext3 and the hard drives we
use, we have not yet needed the backups for that.
Journaling no protection against power drop