RAID-1 and bad sectors?

In SCSI RAID 1/5, the drives often have bad sector reallocation turned off.
The RAID firmware regenerates the data when a bad sector shows up,
issues a REASSIGN command, and writes the correct data to a fresh sector.

SATA-2 probably can do the same thing, but more likely ATA/SATA RAID
just rewrites the correct data and the drive reallocates automagically.

wrote in message ...

Anyways, I'm now ready to set up RAID-1 in my system. But I'm wondering if
that bad sector might cause a problem in a RAID-1 setup? I know RAID-1 is
supposed help you if a drive fails. But what if a drive doesn't totally stop
working... what if it only develops a few bad sectors? Can RAID-1 handle
that? (I'll be using the HighPoint 370 controller on my Abit KT7-RAID
motherboard.) Like what would happen if the RAID controller is writing some
data, and one of the drives is OK but the other drive has some bad sectors on
it? Can the RAID controller detect the bad sectors and write the data to good
sectors? Or will it not detect the bad sectors and the 2 drives will be
out-of-sync?

I have a Samsung SP1213N 120 GB drive, and on their web site they have a
couple utilities for testing hard drives: SHDIAG, which asks you to do a
low-level format if it detects an error (I guess I don't want to use that
one), and HUTIL. They don't say what HUTIL does if it detects an error, but
they say it writes stuff to the disk while testing. Would it overwrite any of
my data?


Hi,

I ran HUTIL on my Samsung SP2014N a couple of weeks ago, and when it
found what it said was a bad sector, I think that the warning msg said
that it would write all zeroes to that sector if I answer 'yes'. I was
right in the middle of a bunch of things, so I don't remember exactly,
but I know that I decided NOT to tell it 'yes'.

Jim

OK, I just ran HUTIL and got some errors (see below). Is there any way to
tell if those bad sectors have data on them or if they're not being used?



[SELF DIAGNOSTIC (Hutil v2.00)]
Model Name : SAMSUNG SP1213N
Rom Revision : TL100-24
Drive Size : 114498MB (LBA : 234493056)
Start Time : Fri Dec 30 20:57:49 2005


-------------------------------------------------
Test Loop Number : 1/1
-------------------------------------------------
READ DMA : Testing... Pass !
CHECK M.C. : Testing... Pass !
CHECK S.M.A.R.T. : Testing... Pass !
SPIN DOWN / UP : Testing... Pass !
SIMPLE READ / WRITE : Testing... Pass !
SIMPLE SURFACE SCAN : Testing... Pass !
WRITE VERIFY : Testing... Pass !
AVERAGE SEEK TIME : Testing... Pass !
MAXIMUM SEEK TIME : Testing... Pass !
RANDOM SURFACE SCAN : Testing... Pass !
READ SURFACE SCAN : Testing...
C:42962 H:0 S:547 Error : Ecc error
C:42962 H:0 S:548 Error : Ecc error
C:42962 H:0 S:549 Error : Ecc error
C:42962 H:0 S:550 Error : Ecc error
C:42962 H:0 S:551 Error : Ecc error
C:42962 H:0 S:552 Error : Ecc error
C:42962 H:0 S:553 Error : Ecc error
C:42962 H:0 S:554 Error : Ecc error
C:42962 H:0 S:555 Error : Ecc error
C:42962 H:0 S:556 Error : Ecc error
C:42962 H:0 S:557 Error : Ecc error
C:42962 H:0 S:558 Error : Ecc error
C:42962 H:0 S:559 Error : Ecc error
C:42962 H:0 S:560 Error : Ecc error
C:42962 H:0 S:561 Error : Ecc error
C:42962 H:0 S:562 Error : Ecc error
C:42962 H:0 S:563 Error : Ecc error
C:42962 H:0 S:564 Error : Ecc error
C:42962 H:0 S:565 Error : Ecc error
C:42962 H:0 S:566 Error : Ecc error
C:42962 H:0 S:567 Error : Ecc error
C:42962 H:0 S:568 Error : Ecc error
C:42962 H:0 S:569 Error : Ecc error
C:42962 H:0 S:570 Error : Ecc error
C:42962 H:0 S:571 Error : Ecc error
C:42962 H:0 S:572 Error : Ecc error
C:42962 H:0 S:573 Error : Ecc error
C:42962 H:0 S:574 Error : Ecc error
C:42962 H:0 S:575 Error : Ecc error
C:42962 H:0 S:576 Error : Ecc error
C:42962 H:0 S:577 Error : Ecc error
C:42962 H:0 S:578 Error : Ecc error
Error : This drive has some defects.

Scan Elapsed Time : 00:41:49
Error Occured Test Loop Number 1
End Time : Fri Dec 30 21:41:55 2005
Test was completed.
=================================================

wrote

OK, I just ran HUTIL and got some errors (see below).
Is there any way to tell if those bad sectors have data
on them or if they're not being used?

Hitachi's DFT does tell you what files particular bads are in
from memory. Dont currently have a drive with bads to check.

Why do you care ? You said you have the data fully backed up.

It would be worth checking the drive with some other diag like
DFT, those numbers look suspicious, all at the extreme range
of the cylinders, all on one head, with increasing sector numbers.

I'd personally get the SMART data somehow, by using
smartctl when using the knoppix CD and decide whether
to RMA the drive if its clearly failing, like it looks like it is.

If the data is fully backed up, I'd personally write zeros thru the
drive and see if that will get the drive to reallocate the bads, but
thats too many bads for my taste, it looks like its dying.

[SELF DIAGNOSTIC (Hutil v2.00)]
Model Name : SAMSUNG SP1213N
Rom Revision : TL100-24
Drive Size : 114498MB (LBA : 234493056)
Start Time : Fri Dec 30 20:57:49 2005


-------------------------------------------------
Test Loop Number : 1/1
-------------------------------------------------
READ DMA : Testing... Pass !
CHECK M.C. : Testing... Pass !
CHECK S.M.A.R.T. : Testing... Pass !
SPIN DOWN / UP : Testing... Pass !
SIMPLE READ / WRITE : Testing... Pass !
SIMPLE SURFACE SCAN : Testing... Pass !
WRITE VERIFY : Testing... Pass !
AVERAGE SEEK TIME : Testing... Pass !
MAXIMUM SEEK TIME : Testing... Pass !
RANDOM SURFACE SCAN : Testing... Pass !
READ SURFACE SCAN : Testing...
C:42962 H:0 S:547 Error : Ecc error
C:42962 H:0 S:548 Error : Ecc error
C:42962 H:0 S:549 Error : Ecc error
C:42962 H:0 S:550 Error : Ecc error
C:42962 H:0 S:551 Error : Ecc error
C:42962 H:0 S:552 Error : Ecc error
C:42962 H:0 S:553 Error : Ecc error
C:42962 H:0 S:554 Error : Ecc error
C:42962 H:0 S:555 Error : Ecc error
C:42962 H:0 S:556 Error : Ecc error
C:42962 H:0 S:557 Error : Ecc error
C:42962 H:0 S:558 Error : Ecc error
C:42962 H:0 S:559 Error : Ecc error
C:42962 H:0 S:560 Error : Ecc error
C:42962 H:0 S:561 Error : Ecc error
C:42962 H:0 S:562 Error : Ecc error
C:42962 H:0 S:563 Error : Ecc error
C:42962 H:0 S:564 Error : Ecc error
C:42962 H:0 S:565 Error : Ecc error
C:42962 H:0 S:566 Error : Ecc error
C:42962 H:0 S:567 Error : Ecc error
C:42962 H:0 S:568 Error : Ecc error
C:42962 H:0 S:569 Error : Ecc error
C:42962 H:0 S:570 Error : Ecc error
C:42962 H:0 S:571 Error : Ecc error
C:42962 H:0 S:572 Error : Ecc error
C:42962 H:0 S:573 Error : Ecc error
C:42962 H:0 S:574 Error : Ecc error
C:42962 H:0 S:575 Error : Ecc error
C:42962 H:0 S:576 Error : Ecc error
C:42962 H:0 S:577 Error : Ecc error
C:42962 H:0 S:578 Error : Ecc error
Error : This drive has some defects.

Scan Elapsed Time : 00:41:49
Error Occured Test Loop Number 1
End Time : Fri Dec 30 21:41:55 2005
Test was completed.
=================================================

On Sat, 31 Dec 2005 16:53:01 +1100, "Rod Speed" wrote:

wrote

OK, I just ran HUTIL and got some errors (see below).
Is there any way to tell if those bad sectors have data
on them or if they're not being used?

Hitachi's DFT does tell you what files particular bads are in
from memory. Dont currently have a drive with bads to check.

Why do you care ? You said you have the data fully backed up.

If I can determine that those bad sectors are in unused areas, then I can
"ghost" the drive to my new SP1213N, which I also ran HUTIL on and it has no
problems. That's much easier than spending time to re-install the OS and
re-install and re-configure a ton of applications.

I also need to determine how BootItNG deals with writing data to bad sectors,
and how Windows deals with reading and writing data from bad sectors. That
will help me determine if my data still has integrity or not.


It would be worth checking the drive with some other diag like
DFT, those numbers look suspicious, all at the extreme range
of the cylinders, all on one head, with increasing sector numbers.

I'd personally get the SMART data somehow, by using
smartctl when using the knoppix CD and decide whether
to RMA the drive if its clearly failing, like it looks like it is.

What will the SMART data tell me?


If the data is fully backed up, I'd personally write zeros thru the
drive and see if that will get the drive to reallocate the bads, but
thats too many bads for my taste, it looks like its dying.

The reviews on newegg.com for these Samsung drives aren't great. I have no
confidence that my new SP1213N won't develop the same problems.

wrote
Rod Speed wrote
wrote

OK, I just ran HUTIL and got some errors (see below).
Is there any way to tell if those bad sectors have data
on them or if they're not being used?

Hitachi's DFT does tell you what files particular bads are in
from memory. Dont currently have a drive with bads to check.

Why do you care ? You said you have the data fully backed up.

If I can determine that those bad sectors are in unused areas, then
I can "ghost" the drive to my new SP1213N, which I also ran HUTIL
on and it has no problems. That's much easier than spending time to
re-install the OS and re-install and re-configure a ton of applications.

OK.

I also need to determine how BootItNG deals with writing data to bad sectors,

The hard drive should handle that behind BootItNG's back.

and how Windows deals with reading and writing data from bad sectors.

The hard drive should handle the writing behind Win's back.

That will help me determine if my data still has integrity or not.

It would be worth checking the drive with some other diag like
DFT, those numbers look suspicious, all at the extreme range
of the cylinders, all on one head, with increasing sector numbers.

I'd personally get the SMART data somehow, by using
smartctl when using the knoppix CD and decide whether
to RMA the drive if its clearly failing, like it looks like it is.

What will the SMART data tell me?

Basically confirm that the drive is dying.

If the data is fully backed up, I'd personally write zeros thru
the drive and see if that will get the drive to reallocate the bads,
but thats too many bads for my taste, it looks like its dying.

The reviews on newegg.com for these Samsung drives aren't great.

I've never believed those reviews myself.

I have no confidence that my new SP1213N
won't develop the same problems.

None of mine have. And the storagereview reliablity database
shows that plenty dont have any problems with their drives too.

And the result with many of their competitors drives are
much worse, particularly the maxtor drives of the same size.

The seagate 7200.7s do better, but the 7200.8s are obscenely bad.

Rod Speedwrote:
wrote

And the result with many of their competitors drives are
much worse, particularly the maxtor drives of the same size.

The seagate 7200.7s do better, but the 7200.8s are obscenely bad.

I'm curious, where did you read that about the Maxtors? Please post
the link.

On Sat, 31 Dec 2005 17:46:49 +1100, "Rod Speed" wrote:

I also need to determine how BootItNG deals with writing data to bad sectors,

The hard drive should handle that behind BootItNG's back.

and how Windows deals with reading and writing data from bad sectors.

The hard drive should handle the writing behind Win's back.

So the hard drive will detect a bad sector and then find a good sector to
which to write the data? Based on what Chuck F. said, the hard drive will
just write the data to whichever sector, even if its bad.


What will the SMART data tell me?

Basically confirm that the drive is dying.

Seems like a safe assumption.


I have no confidence that my new SP1213N
won't develop the same problems.

None of mine have. And the storagereview reliablity database
shows that plenty dont have any problems with their drives too.

And the result with many of their competitors drives are
much worse, particularly the maxtor drives of the same size.

The seagate 7200.7s do better, but the 7200.8s are obscenely bad.

Thanks for pointing out storagereview.com. Looks like the Samsungs are near
the bottom third. The Seagate 7200.7s are near the top. Maybe I'll get a
couple of those.

Thanks for the informative post, Arno.

wrote
Rod Speed wrote

I also need to determine how BootItNG
deals with writing data to bad sectors,

The hard drive should handle that behind BootItNG's back.

and how Windows deals with reading and writing data from bad sectors.

The hard drive should handle the writing behind Win's back.

So the hard drive will detect a bad sector and then
find a good sector to which to write the data?

Yes.

Based on what Chuck F. said, the hard drive will just
write the data to whichever sector, even if its bad.

Its more complicated than that.

What will the SMART data tell me?

Basically confirm that the drive is dying.

Seems like a safe assumption.

It aint about assumptions. You can get what
appear to be bad sectors for other reasons.

I have no confidence that my new SP1213N
won't develop the same problems.

None of mine have. And the storagereview reliablity database
shows that plenty dont have any problems with their drives too.

And the result with many of their competitors drives are
much worse, particularly the maxtor drives of the same size.

The seagate 7200.7s do better, but the 7200.8s are obscenely bad.

Thanks for pointing out storagereview.com.
Looks like the Samsungs are near the bottom third.

There's plenty in the bottom 10%

The Seagate 7200.7s are near the top. Maybe I'll get a couple of those.