![]() ![]() I do not know whether a standard (non-secure) erase with Disk Utility. I think a "reformat" would only accomplish something if the format wrote to every sector on the drive. (BTW, do you mean TechTool Deluxe 3.1.3?) Since TechTool probably didn't try to write the sector, it was not (yet) reallocated. The sector read error most likely occured during the disk scan you did earlier with TechTool. So if the above is true then apparently the Pending Sector Count needs to be interpreted cautiously. Read errors on a sector will not remap the sector (since it might be readable later) instead, the drive firmware remembers that the sector needs to be remapped, and remaps it the next time it's written. If an unstable sector is subsequently written or read successfully, this value is decreased and the sector is not remapped. Number of "unstable" sectors (waiting to be remapped, because of read errors). Thus, the higher the attribute value, the more sectors the drive has had to reallocate. The raw value normally represents a count of the number of bad sectors that have been found and remapped. However, as the number of reallocated sectors increases, the read/write speed tends to decrease. This is why, on modern hard disks, "bad blocks" cannot be found while testing the surface – all bad blocks are hidden in reallocated sectors. This process is also known as remapping, and "reallocated" sectors are called remaps. When the hard drive finds a read/write/verification error, it marks this sector as "reallocated" and transfers data to special reserved area (spare area). ![]() Note what it says in the table in the Wikipedia S.M.A.R.T. The drive's firmware is supposed to do it automagically on its own. My understanding is that you would not do it. So, how do you change a "pending" bad sector to a "removed" or "reallocated" one? )Ĭuriously, SMART Utility calls the drive "Failing" when all other utilities show it as "Verified". On the other hand, SMARTReporter IS free. The keyboard shortcuts & mouse "right-click" context window won't do it. attributes".Īnother SMARTReporter quirk is that cut'n paste apparently only works in these display windows when you use the menu bar entries. Yes, starting with version 2.4.5! Right-click the drive in the drive-list in the preferences window and select "Check S.M.A.R.T. In the SMARTReporter FAQ you can find this tidbit:Ĭan SMARTReporter tell me exactly which S.M.A.R.T. registers, you just have to jump through unexpected hoops to do it. You can in fact query & display the contents of a drive's S.M.A.R.T. SMARTReporter appears to be a rather "quirky" utility. Perhaps Disk Warrior's "Bad Block" is referring to something else? (I couldn't guess what that might be though). This is the number of bad sector's which the drive has remapped. registers for your drive with a tool like SMARTReporter, you should see an entry with ID number 05 and title "Reallocated Sectors Count". I don't know when it started but some time back the ability to remap a bad sector was merged into the firmware of the hard drive. I doubt you will find any software tools to "fix" bad blocks, at least for recent hardware. What type of a Mac and what type of hard drive are you having problems with? I don't know of any tool that will do a surface scan and fix the bad blocks too. Since you're using Mac OS X, which is based on BSD, you might also want to read up on badsect and bad144, which are the built-in BSD command-line utilities for dealing with bad blocks. ![]() You can get a list of all hard disks (/dev/sdX devices) by typing this command: sudo fdisk -l If you have more than one hard drive, you can replace /dev/sda with /dev/sdX, where X is lowercase letter. This will do a non-destructive random read-write test on the first drive, remapping bad sectors along the way. The easiest way to force the drive to do its own bad block remapping is to boot from an Ubuntu Live CD, then open a terminal and run this command: sudo badblocks -nvs /dev/sda (Note: make sure to backup your data first!) If the SMART diagnostics are reporting no reallocated sectors (or if the VALUE column for "Reallocated Sector Count" is still well below THRESHOLD), there is an easy way to perform a surface scan and remap the bad blocks at the same time. I'd suggest downloading smartmontools and GSmartControl to view the SMART diagnostics as another check, if you aren't sure which SMART diagnostics to trust. You should backup your data immediately (if you haven't already) and replace the drive before the problem gets worse and you lose your data. ![]() If you're seeing bad blocks when you run a filesystem integrity check, the hard drive has most likely already exceeded the number of blocks it can remap, and has exhausted its "spare" sectors. ![]()
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