PC Review


Reply
Thread Tools Rate Thread

chkdsk.exe returns different errors depending on user who runs it

 
 
Florian
Guest
Posts: n/a
 
      27th Feb 2004
I am experiencing interesting behaviour with chkdsk.exe on a Windows 2000
Professional machine (SP4, all patches). This machine has a few NTFS
partitions, all on a RAID5 Adaptec SCSI (shouldn't matter but I thought I'd
mention it anyway).

I'm running a plain chkdsk.exe on a drive as the local Administrator, and
the file system is clean. That is chkdsk.exe does not display an error
messages.

Then, I'm running the EXACT same command under the "Task Manager" with a
scheduled task. Hence, the command is executed under the LOCALSYSTEM
account. Interestingly enough, the chkdsk.exe run shows errors this time,
such as:

CHKDSK discovered free space marked as allocated in the master file table
(MFT) bitmap.
CHKDSK discovered free space marked as allocated in the volume bitmap.

Windows found problems with the file system.

So, depending on whether I run chkdsk.exe under the Administrator or
LOCALSYSTEM account, I get different results.

Note that these results are persistent - that is running chkdsk.exe under
the Administrator account will NEVER show any errors, while running under
the LOCALSYSTEM account will ALWAYS show up errors (I have not tried running
"chkdsk.exe /F" under the LOCALSYSTEM account yet).

I'm not too worried about potential problems in the file system here, just
curious why this tool is not consistent. I was fairly certain that the
integrity of the file system was not dependent on the permissions of the
user account.

I understand that this is probably quite theoretical, but I have also seen
that chkdsk.exe always returns errors in the Volume Bitmap under Windows XP,
no matter how often one runs chkdsk.exe /f - so I'm starting to wonder how
useful chkdsk.exe is - or how useful NTFS is :-)


Thanks,
Florian.


 
Reply With Quote
 
 
 
 
Phil Barila
Guest
Posts: n/a
 
      29th Feb 2004
"Florian" <(E-Mail Removed)> wrote in message
news:H0N%b.11883$(E-Mail Removed)...
> I am experiencing interesting behaviour with chkdsk.exe on a Windows 2000
> Professional machine (SP4, all patches). This machine has a few NTFS
> partitions, all on a RAID5 Adaptec SCSI (shouldn't matter but I thought

I'd
> mention it anyway).
>
> I'm running a plain chkdsk.exe on a drive as the local Administrator, and
> the file system is clean. That is chkdsk.exe does not display an error
> messages.
>
> Then, I'm running the EXACT same command under the "Task Manager" with a
> scheduled task. Hence, the command is executed under the LOCALSYSTEM
> account. Interestingly enough, the chkdsk.exe run shows errors this time,
> such as:
>
> CHKDSK discovered free space marked as allocated in the master file table
> (MFT) bitmap.
> CHKDSK discovered free space marked as allocated in the volume bitmap.
>
> Windows found problems with the file system.
>
> So, depending on whether I run chkdsk.exe under the Administrator or
> LOCALSYSTEM account, I get different results.
>
> Note that these results are persistent - that is running chkdsk.exe under
> the Administrator account will NEVER show any errors, while running under
> the LOCALSYSTEM account will ALWAYS show up errors (I have not tried

running
> "chkdsk.exe /F" under the LOCALSYSTEM account yet).


Chkdsk without the /f is useless, no matter who runs it. There's just no
way (short of suspending every task in the system, to be sure that someone
else isn't changing the FS and causing the errors. That's why the /f forces
a dismount or reboot.

> I'm not too worried about potential problems in the file system here, just
> curious why this tool is not consistent. I was fairly certain that the
> integrity of the file system was not dependent on the permissions of the
> user account.
>
> I understand that this is probably quite theoretical, but I have also seen
> that chkdsk.exe always returns errors in the Volume Bitmap under Windows

XP,
> no matter how often one runs chkdsk.exe /f - so I'm starting to wonder how
> useful chkdsk.exe is - or how useful NTFS is :-)


Since Win2K SP2, chkdsk has been indicating some benign states as not so
benign. It got much quieter in XP SP1, or maybe some hotfix between XP RTM
and now. The Google groups archive has lots of messages about that from
sometime in the last year and a half. I participated in those threads, so
if you look for my name, it should help you find that information.

Phil
--
Philip D. Barila Windows DDK MVP
Seagate Technology, LLC
(720) 684-1842
As if I need to say it: Not speaking for Seagate.
E-mail address is pointed at a domain squatter. Use reply-to instead.


 
Reply With Quote
 
Florian
Guest
Posts: n/a
 
      1st Mar 2004
Thanks for your reply. I have found the official chkdsk reference for
Windows Server 2003 in the meantime and realized that chkdsk.exe cannot be
trusted if processes are accessing the file system when it runs, only a
chkdsk /f is reliable.

I was just under the impression that the OS should know whether the FS is OK
or not - even when processes are accessing the file system. But then again,
I know too little about FS to really make a case here :-)

Thanks!

"Phil Barila" <(E-Mail Removed)> wrote in message
news:sZydnePmXe5N89_dRVn-(E-Mail Removed)...
> "Florian" <(E-Mail Removed)> wrote in message
> news:H0N%b.11883$(E-Mail Removed)...
> > I am experiencing interesting behaviour with chkdsk.exe on a Windows

2000
> > Professional machine (SP4, all patches). This machine has a few NTFS
> > partitions, all on a RAID5 Adaptec SCSI (shouldn't matter but I thought

> I'd
> > mention it anyway).
> >
> > I'm running a plain chkdsk.exe on a drive as the local Administrator,

and
> > the file system is clean. That is chkdsk.exe does not display an error
> > messages.
> >
> > Then, I'm running the EXACT same command under the "Task Manager" with a
> > scheduled task. Hence, the command is executed under the LOCALSYSTEM
> > account. Interestingly enough, the chkdsk.exe run shows errors this

time,
> > such as:
> >
> > CHKDSK discovered free space marked as allocated in the master file

table
> > (MFT) bitmap.
> > CHKDSK discovered free space marked as allocated in the volume bitmap.
> >
> > Windows found problems with the file system.
> >
> > So, depending on whether I run chkdsk.exe under the Administrator or
> > LOCALSYSTEM account, I get different results.
> >
> > Note that these results are persistent - that is running chkdsk.exe

under
> > the Administrator account will NEVER show any errors, while running

under
> > the LOCALSYSTEM account will ALWAYS show up errors (I have not tried

> running
> > "chkdsk.exe /F" under the LOCALSYSTEM account yet).

>
> Chkdsk without the /f is useless, no matter who runs it. There's just no
> way (short of suspending every task in the system, to be sure that someone
> else isn't changing the FS and causing the errors. That's why the /f

forces
> a dismount or reboot.
>
> > I'm not too worried about potential problems in the file system here,

just
> > curious why this tool is not consistent. I was fairly certain that the
> > integrity of the file system was not dependent on the permissions of the
> > user account.
> >
> > I understand that this is probably quite theoretical, but I have also

seen
> > that chkdsk.exe always returns errors in the Volume Bitmap under Windows

> XP,
> > no matter how often one runs chkdsk.exe /f - so I'm starting to wonder

how
> > useful chkdsk.exe is - or how useful NTFS is :-)

>
> Since Win2K SP2, chkdsk has been indicating some benign states as not so
> benign. It got much quieter in XP SP1, or maybe some hotfix between XP

RTM
> and now. The Google groups archive has lots of messages about that from
> sometime in the last year and a half. I participated in those threads, so
> if you look for my name, it should help you find that information.
>
> Phil
> --
> Philip D. Barila Windows DDK MVP
> Seagate Technology, LLC
> (720) 684-1842
> As if I need to say it: Not speaking for Seagate.
> E-mail address is pointed at a domain squatter. Use reply-to instead.
>
>



 
Reply With Quote
 
Phil Barila
Guest
Posts: n/a
 
      2nd Mar 2004
"Florian" <(E-Mail Removed)> wrote in message
news:FvG0c.13813$(E-Mail Removed)...
> Thanks for your reply. I have found the official chkdsk reference for
> Windows Server 2003 in the meantime and realized that chkdsk.exe cannot be
> trusted if processes are accessing the file system when it runs, only a
> chkdsk /f is reliable.
>
> I was just under the impression that the OS should know whether the FS is

OK
> or not - even when processes are accessing the file system. But then

again,
> I know too little about FS to really make a case here :-)


The short answer for why it can't is that chkdsk can't take a complete
snapshot of the entire FS in a short enough time to guarantee that it's a
fully consistent state. If there's the possibility that any other process
is doing something to the FS, the FS state can change between when chkdsk
starts and when it's done. So the net effect is that even though the FS is
always consistent, chkdsk sees some apparent inconsistencies due to the FS
changing while chkdsk is working.

The long answer is just like that, only more words! :-)

Phil
--
Philip D. Barila Windows DDK MVP
Seagate Technology, LLC
(720) 684-1842
As if I need to say it: Not speaking for Seagate.
E-mail address is pointed at a domain squatter. Use reply-to instead.


 
Reply With Quote
 
Vishal Ghotge [MSFT]
Guest
Posts: n/a
 
      3rd Mar 2004
Windows Server 2003 resource kit has a wonderful tool call "VRFYDSK". This
will create a shadow copy of the volume and run CHKDSK on that shadow copy.
Unfortunately this is not available for W2K.

The resource kit is available for download at:
http://www.microsoft.com/downloads/d...displaylang=en

--
Thanks,
Vishal Ghotge [MSFT]
--
This posting is provided "AS IS" with no warranties, and confers no rights

"Phil Barila" <(E-Mail Removed)> wrote in message
news:Ho2dnephaP653dndRVn-(E-Mail Removed)...
> "Florian" <(E-Mail Removed)> wrote in message
> news:FvG0c.13813$(E-Mail Removed)...
>> Thanks for your reply. I have found the official chkdsk reference for
>> Windows Server 2003 in the meantime and realized that chkdsk.exe cannot
>> be
>> trusted if processes are accessing the file system when it runs, only a
>> chkdsk /f is reliable.
>>
>> I was just under the impression that the OS should know whether the FS is

> OK
>> or not - even when processes are accessing the file system. But then

> again,
>> I know too little about FS to really make a case here :-)

>
> The short answer for why it can't is that chkdsk can't take a complete
> snapshot of the entire FS in a short enough time to guarantee that it's a
> fully consistent state. If there's the possibility that any other process
> is doing something to the FS, the FS state can change between when chkdsk
> starts and when it's done. So the net effect is that even though the FS
> is
> always consistent, chkdsk sees some apparent inconsistencies due to the FS
> changing while chkdsk is working.
>
> The long answer is just like that, only more words! :-)
>
> Phil
> --
> Philip D. Barila Windows DDK MVP
> Seagate Technology, LLC
> (720) 684-1842
> As if I need to say it: Not speaking for Seagate.
> E-mail address is pointed at a domain squatter. Use reply-to instead.
>
>



 
Reply With Quote
 
=?Utf-8?B?TWljaGFlbCBXYWx0cmlw?=
Guest
Posts: n/a
 
      4th Mar 2004
Interesting. I'm replying with reading the other replies here, but I just posted a Chkdsk problem and found this while waiting

Haven't tried it (Chkdsk) under local admin, but account used in admin group

While poking around I had another hunch. Something to do with the Recycle bin settings. Changing this (one setting for all drives, and back), all worked for my normal login account. When logged in ad local admin, I guess had files left in the bin, as it said "Recycle bin invalid", do you want to empty and reconfigure? Said yes, but when I did I started seeing errors like this

Windows will now check the disk.
Cleaning up minor inconsistencies on the drive
Cleaning up 1 unused index entries from index $SII of file 0x9
Cleaning up 1 unused index entries from index $SDH of file 0x9
Cleaning up 1 unused security descriptors

And regular (it always finds 1 to 5 of these). Other hunch was Frequent Defrag releated)

Do you defrag often (or when it says you don't have enough free space)
Have you changed Recycle Bin settings recently

 
Reply With Quote
 
 
 
Reply

Thread Tools
Rate This Thread
Rate This Thread:

Posting Rules
You may not post new threads
You may not post replies
You may not post attachments
You may not edit your posts

BB code is On
Smilies are On
[IMG] code is On
HTML code is Off
Trackbacks are On
Pingbacks are On
Refbacks are Off


Similar Threads
Thread Thread Starter Forum Replies Last Post
Macro in add-in runs depending on if sheet exists in workbook JC Microsoft Excel Programming 2 18th Nov 2008 05:51 PM
User account shutdown, chkdsk runs Gary I. Windows XP Performance 2 26th Feb 2008 05:02 AM
chkdsk never runs brsfan Windows Vista General Discussion 3 29th Jan 2008 04:35 AM
chkdsk- useless-scandisk found errors-chkdsk did not =?Utf-8?B?UmljayBI?= Windows XP Help 4 19th Oct 2005 09:28 PM
Chkdsk Re-Runs, Over and Over Angst Windows XP Help 1 19th Feb 2005 12:21 AM


Features
 

Advertising
 

Newsgroups
 


All times are GMT +1. The time now is 12:06 AM.