SMART Not So SMART?

Question

Some weeks ago my PowerBook hard disk showed some bad sectors. Trying to repair it with Disk Warrior, TechTools and Disk Utility all had mixed results. THEN Disk Utility reported that SMART had reported a Fatal failure. After that none of the utilities could repair the disk. I could not even format it anymore in Disk Utility. Disk Warrior had nothing to repair. I was ready to go buy a new hard disk (read separate thread on using 160GB internal to replace 80GB original).
But, before spending almost $400-500 I was able to force mounth the disk, and use one of the utilities to write zeros in all the blank space. That worked. THEN I reformatted the drive and used Erase space with Zeroes option (hoping to remove/lock out bad sectors). THEN I cloned data back and have been using the machine since then and SMART reports the disk is Verified and Healthy.
So, I am not sure if I am just pushing my luck (though backing up my data every 24 hours) or if SMART is just not that SMART and can report FATAL failures while the disk may be fine....
Opinions, experiences? Let me know... Will report if it actually fails.
Imran

Answer 1

Imran--
c- TechTool Pro DOES show bad blocks in a surface
scan, but I believe that utility shows what is on the
physical drive, and not what the OS makes available
for use. In other words, TechTools will probably
always tell that Bad Blocks Exist.
Actually, from reading around, and from experience, I think this is not such a good sign. On the PowerBook I had, once I reformatted and wrote zeros, neither TechTool Pro nor smartmontools showed any bad blocks any more. smartmontools just showed the previously re-allocated sectors in its report. So I think that the fact that TechTool Pro still shows bad blocks is a sign it's still shedding magnetic media.
The reallocated sector information is actually stored in the drive's firmware, so any attempt to read or write to the bad sector just sends the drive's head to the spare sector. So, if it was able to remap all the bad sectors, a surface scan shouldn't show any bad blocks.
d- I slowly started moving my data back to the
PowerBook and am backing up everything, everyday. So
far, no problems, except the dreaded nightmare of mds
spotlight process having taken over the machine for
24 HOURS. Even looking for a specific file by
specific name in Finder that I typed in 4 HOURS ago
is still spinning. I HATE MDS and I hope the creator
of the obnoxious behavior of mds/spotlight suffers
pain of some sort or the other... curses on them...
note to self, buy voodoo dolls and pins.
Ah, but if your drive isn't healthy, then that could explain the Spotlight problem. My PowerBook doesn't stall out and get taken over by Spotlight's indexing. I don't remember it taking more than an hour or so to index my drive. I frankly never notice it except when I attach an external FireWire drive that's never been attached before.
f- I am comfortable compiling stuff, though never had
the opportunity to do that on Mac OS X.
Well, if you have Xcode installed, if I remember correctly, it's just the usual download the source, unpack the archive, then ./configure, and make steps. I don't remember anything unusual about it, anyway.
SHOULD have bought 10000 Apple shares at
$7 back then
Heh, heh, yep. I remember saying almost exactly the same thing.
h- I would love to try to compile this smartmontools
app, but would it give me any more info/utility than
I already see in TechTools?
I don't remember what TechTool shows, but this page has an example report (with a drive failing because of a reallocated sector count).
charlie