file corruption after disk got too full

[Rob]

Hello,
Here's the scenario:
2003 server, RAID 5 with 2 partitions. D partition had 1 huge folder (about
500GB), and partition itself was about 535GB. Data grew unexpectedly & got
up to about 534GB. Got errors in event logs pertaining to disk full, and
immediately moved folder to partition with more room using Xcopy.
Have since discovered that corruption did occur randomly in some sub
folders. Files are mostly .dwg & .pdf files.

If I run a scan disk on the new partition where the data was moved to, could
it possibly repair some of these corrupted files?
New partition is on a DAS & is about 2.1TB in size, so chkdsk would take a
long time to run...

If it wouldn't fix them, does any one know of any utilities that could :
-locate corrupted files
-repair .pdf & .dwg files

Backups have been spotty lately, and I don't have a good complete backup
that doesn't have any corruption on it....

Thanks!

Rob

 

[Edwin vMierlo [MVP]]

response in-line

> Have since discovered that corruption did occur randomly in some sub
> folders. Files are mostly .dwg & .pdf files.

How did you discover this ?

>
> If I run a scan disk on the new partition where the data was moved to,
could
> it possibly repair some of these corrupted files?

no scan disk and chkdsk will not repair file corruption, it will *try* to
repair the NTFS file-system (e.g. data-structures) to a consistent state,
but will not touch any files or content of files.

From http://support.microsoft.com/kb/187941 :

"It should be pointed out that NTFS does not guarantee the integrity of user
data following an instance of disk corruption -- even when a full CHKDSK is
run immediately after corruption has been detected. Thus, there may be files
that CHKDSK cannot recover. Also, files that are recovered may be internally
corrupted even after CHKDSK has been run."

> New partition is on a DAS & is about 2.1TB in size, so chkdsk would take a
> long time to run...

yep, I would recommend smaller NTFS volumes and spread the data around.

Smaller volumes Pro:
- when corrupted, chkdsk is faster
- when corrupted, you do not have to take all your shares/volumes offline
Smaller volumes Con:
- requires the admin to actually actively manage storage

Large volumes Pro:
- requires less admin / management
Large volumes Con:
- when corrupted, chkdsk takes a very long time
- you need to take all your shares/folders offline, even when corruption
only occurs in a small part


>
> If it wouldn't fix them, does any one know of any utilities that could :
> -locate corrupted files
> -repair .pdf & .dwg files

If the corruption is logically in the file, there are no utilities, other
than from the program who wrote the file in the first place, e.g. if this is
an outlook file, then outlook has to have a utility to check and repair its
own files (and it has btw, hence I choose this as an example)

>
> Backups have been spotty lately, and I don't have a good complete backup
> that doesn't have any corruption on it....

well, that is a different topic, I won't state the obvious, but do put this
on your priority list !

HTH,
Edwin.