Sid Spry wrote: > > On Tue, Jun 23, 2020, at 12:26 PM, Dale wrote: >> SMART can't predict the future so it can only monitor for the things >> it can see. If say a spindle bearing is about to lock up suddenly, >> SMART most likely can't detect that since it is a hardware failure that >> can't really be predicted. We may be able to hear a strange sound if we >> lucky but if it happens suddenly, it may not even do that. While SMART >> can't predict all points of failures, it can detect a lot of them. Even >> if the two drives I had failed with no warning from SMART, I'd still >> run it and monitor it. Using SMART can warn you in certain situations. >> If a person doesn't run SMART, they will miss those warnings. >> >> SMART isn't perfect but it is better than not having it all. >> > Well, in theory SMART should be able to predict hardware failures like > that through N-th order effects that percolate up to read and write > statistics. In practice it seems to be guessing badly. > > The danger of SMART is that rate of false negatives is so high (IME) that > you might erroneously think a drive is not going to fail and putting off a > backup. A good backup policy should mitigate this, but you still might plan > around drive lifetime SMART predicts before realizing they are or can be > bad predictions. > >
Thing is, drives fail at some point. SMART, while not perfect, can detect problems that indicate a failure. Let's say for example a person because of the false positives decides not to run SMART at all. What are they going to use to figure out if a drive is working like it should? Is a drive having problems reading, writing or noticing corrupt data that is a sign of a problem? Is it about to fail somehow? It's not like there is really any other tool that does this. if one doesn't use the tool, they can have a failure that they could have been warned about and not lose data or very little data. If a person runs it tho, at least they have something that can detect some failures and prevent data loss. It's safer to run SMART and get notified when it detects a problem than it is to not run it and have no way of knowing there is a problem at all. Sure, backups are something everyone should do for important data. I have backups here, multiple backups of some data. Still, I run SMART and pay attention to the emails it sends when something is not right. In the past, it has saved me from data loss. I'm sure there is many false positives out there but ignoring the real positives isn't a good solution either. By all means, if one wants to just wing it and hope for the best, disable SMART and take the risk. At some point, a drive will fail and without SMART, likely with no warning at all, not even a false one. ;-) Dale :-) :-)
