Hard drive SMART status: do I need to replace the drive?

Question

Recently I checked my PowerBook's hard drive with Disk Utility, and I got "invalid node structure"--an unfixable error. I backed everything up, reformatted the disk, and copied my files back onto it, and this time Disk Utility reported no error. Disk Utility said the SMART status was "Verified" both before and after, so I wasn't worried.
However, to make sure the hard drive was okay, I installed smartmontools (the command-line SMART data monitoring program, which I got from MacPorts) to get more detailed information. I got the following scary-looking output (sorry the columns are a mess; I can't figure out how to preserve the spacing):
Vendor Specific SMART Attributes with Thresholds:
ID# ATTRIBUTE_NAME FLAG VALUE WORST THRESH TYPE UPDATED WHEN_FAILED RAW_VALUE
1 RawRead_ErrorRate 0x000f 100 100 046 Pre-fail Always - 87253
2 Throughput_Performance 0x0005 100 100 030 Pre-fail Offline - 26542080
3 SpinUpTime 0x0003 100 100 025 Pre-fail Always - 1
4 StartStopCount 0x0032 098 098 000 Old_age Always - 8090
5 ReallocatedSectorCt 0x0033 100 100 024 Pre-fail Always - 8585639690241
7 SeekErrorRate 0x000f 100 100 047 Pre-fail Always - 4052
8 SeekTimePerformance 0x0005 100 100 019 Pre-fail Offline - 0
9 PowerOnSeconds 0x0032 084 084 000 Old_age Always - 8422h25m28s
10 SpinRetryCount 0x0013 100 100 020 Pre-fail Always - 0
12 PowerCycleCount 0x0032 099 099 000 Old_age Always - 6781
192 Power-OffRetractCount 0x0032 100 100 000 Old_age Always - 44
193 LoadCycleCount 0x0032 079 079 000 Old_age Always - 215270
194 Temperature_Celsius 0x0022 100 100 000 Old_age Always - 43 (Lifetime Min/Max 11/49)
195 HardwareECCRecovered 0x001a 100 100 000 Old_age Always - 82
196 ReallocatedEventCount 0x0032 100 100 000 Old_age Always - 287047681
197 CurrentPendingSector 0x0012 100 100 000 Old_age Always - 1
198 Offline_Uncorrectable 0x0010 099 099 000 Old_age Offline - 2
199 UDMACRC_ErrorCount 0x003e 200 200 000 Old_age Always - 0
200 MultiZone_ErrorRate 0x000f 100 100 060 Pre-fail Always - 23714
203 RunOutCancel 0x0002 100 099 000 Old_age Always - 3728108027884
The main thing I'm worried about is that some of these statistics are in the "Pre-fail" range--does that mean something really bad? I got my PowerBook in 2004, so the hard drive is old anyway; I assume there is a good chance of a problem some time soon. But how worried should I be?
Message was edited by: k49

Answer 1

k49:
I concur with a brody on the S.M.A.R.T Status. The problem you experienced with your drive initially was a directory issue which would have been corrected by Disk Utility or TechTool Pro. However, reformatting, though the ultimate intrusive method, will certainly do the trick.
The key, not only in your case but always, is to make sure you have an up-to-date backup of your entire HDD. The best solution would be to backup to an external firewire drive making a bootable clone using SuperDuper, Carbon Copy Cloner, or Disk Utility.
In addition, if you are nervous about the drive I would keep an eye on it. Run Repair Disk from the installer disk at least weekly to catch any developing issues. You may also want to start researching suitable internal drives, in case you need one, although I would not buy one until you need it. Should your HDD fail, you can then use your bootable clone to format your new HDD, and clone everything back.
Cheers
cornelius