[Coco] OT: Help with horrible bad NAS purchase, Linux EXT3 file system blindly used.

[Aaron Wolfe]

If you're willing to take the thing apart, you should be able to plug
the drives directly into a computer and use standard diagnostic tools.

Hard drives often keep useful statistics and diagnostic information
about themselves which can be accessed with tools like:
http://sourceforge.net/apps/trac/smartmontools/wiki

EXT3 does utilize a list of bad blocks. To my knowledge the linux ext3
implementation does not actually manage this list, instead there are
external tools for creating,  viewing and manipulating this list. In
linux the standard tool is called "badblocks".  If your NAS is running
linux, then it may work the same way or use the same tools.  However,
just because it uses an EXT3 filesystem does not mean that it is
actually running Linux.  EXT3 is a standard that has been implemented
on many operating systems, so the ext3 software in your device might
work differently.

Your drive itself probably also tracks bad blocks and maps requests
for them to spare good blocks.  This may be happening "in the
background" where the nas software doesn't even know about it.  the
SMART tools mentioned above can query the drive controller and find
out about these things.

EXT3 is an extremely reliable and capable filesystem.  It sounds like
you're just getting some junk drives.  If the seller won't accept a
return, you could probably replace the disks with better quality ones
and still use the enclosure.

Good luck
-Aaron


On Sun, Dec 6, 2009 at 12:22 AM, Stephen H. Fischer
<SFischer1 at mindspring.com> wrote:
> OT: Help with horrible bad NAS purchase, Linux EXT3 file system blindly
> used.
>
> Hi,
>
> I am looking for help in deciding what to do with my Maxtor Central Axis (2
> TB) Network Attached Storage unit (NAS).
>
> I was searching the web for information again and realized that there might
> be someone here who knows all about Linux and the EXT3 file system who might
> be able to help me.
>
> The device has two 1TB drives and can be operated in Mirror mode (1TB) or
> Linear mode (2TB).
>
> The file system used is Linux EXT3 but my only access is via a web interface
> that offers very little information and very little control. Only by reading
> forum messages did I learn that Linux EXT3 is used.
>
> Purchased from Microcenter, the first unit was almost DOA. I spent a lot of
> time before realizing
> that the unit had to be returned. So I shipped it off to Mexico at a cost of
> ~ $35.
>
> I got a replacement unit but one of the drives died 5 days later. So I
> shipped it off to Mexico at a cost of ~ $12, Seagate paid the shipping, the
> UPS store provided part of the expensive packaging which was required.
>
> The replacement worked for  a few weeks:
>
> 2009-09-23T22:34:16-0700 This is a Notification Test E-mail
> 2009-11-26T14:42:20-0800 A drive configuration error has been reported for
> the Maxtor Central Axis MCA-05B195..
>
> The second line is all that I get via E-mail from the drive when it has an
> error, the server at Seagate I am sure gets a lot more information which I
> cannot get and they will never admit they have (Except to users who have >
> 10,000 units in service.)
>
> After the Thanksgiving day failure I was able to rebuild the Mirror
> successfully without loss of data.
>
> I got a second Drive Failure message Friday:
>
> 2009-12-04T21:44:16-0800 A drive configuration error has been reported for
> the Maxtor Central Axis MCA-05B195..
>
> Again I was able to rebuild the Mirror successfully without loss of data.
> ----------------------------------
> My question is, does the Linux EXT3 file system map out the failed sectors
> so that they are not used again.
>
> Thus if I stick with the current drives in the unit I will get to a point
> where no more errors will occur and I can trust that my data is safe.
>
> (The data consists of several computer backups which can be recreated, and
> lots of TV Capture Video. (Darn that wonderful "CW_EPG" scheduling program.)
> ----------------------------------
>
> I realize that this is OT and I am very willing to take the discussion
> elsewhere or via private E-mail. I have done a lot of research, posted a
> detailed set of messages on the Seagate forum and can provide some more
> information from the screen shots I have taken to retain some of the
> information the web interface provides but does not allow you to save.
>
> TIA to one and all.
>
> Stephen H. Fischer
>
>
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