where does Dirty Bit exsist in partition ?

NTDEV
1

When Windows system experienced power off accidently, there will be a disk scan after restarting.

MSDN said: when the system started ,it checked out the Direty Bit in partition, the disk scan will begin.

ensample:
chkntfs C: {This would manually schedule a chkdsk on C: on the next
boot - the dirty bit is set for C:}

2

xxxxx@gmail.com wrote:

When Windows system experienced power off accidently, there will be a disk scan after restarting.

MSDN said: when the system started ,it checked out the Direty Bit in partition, the disk scan will begin.

ensample:
chkntfs C: {This would manually schedule a chkdsk on C: on the next
boot - the dirty bit is set for C:}

Why do you want to know? It’s a bit in the master file table (MFT).
You can’t possibly hope to manipulate this bit manually. You can check
and set the bit using the “fsutil” utility:
fsutil dirty query C:
fsutil dirty set C:

–
Tim Roberts, xxxxx@probo.com
Providenza & Boekelheide, Inc.

3

I did a very small amount of digging on google and came up with these. I
can’t vouch for this information, just found it on google.

http://www.withinwindows.com/2007/09/17/setting-ntfs-dirty-bit-without-using-fsutil/
http://technet2.microsoft.com/windowsserver/en/library/3dd141a8-57b8-4bd8-81dd-69c515fd059f1033.mspx?mfr=true

If your in a volume upper filter for example, I’d take a look at the IOCTL
codes that are passing your way when you run

fsutil dirty query.

Chris

“Tim Roberts” wrote in message news:xxxxx@ntdev…
> xxxxx@gmail.com wrote:
>> When Windows system experienced power off accidently, there will be a
>> disk scan after restarting.
>>
>> MSDN said: when the system started ,it checked out the Direty Bit in
>> partition, the disk scan will begin.
>>
>> ensample:
>> chkntfs C: {This would manually schedule a chkdsk on C: on the next
>> boot - the dirty bit is set for C:}
>
> Why do you want to know? It’s a bit in the master file table (MFT). You
> can’t possibly hope to manipulate this bit manually. You can check and
> set the bit using the “fsutil” utility:
> fsutil dirty query C:
> fsutil dirty set C:
>
> –
> Tim Roberts, xxxxx@probo.com
> Providenza & Boekelheide, Inc.
>
>

4

> Why do you want to know? It’s a bit in the master file table (MFT).

In MFT for NTFS, in boot sector for FAT

–
Maxim Shatskih, Windows DDK MVP
StorageCraft Corporation
xxxxx@storagecraft.com
http://www.storagecraft.com

5

My understanding is that any ioctl that notifies the NTFS driver to mark
the FS dirty should not go down any further to the volume stack.

Harish

-----Original Message-----
From: Chris Hall [mailto:xxxxx@situssoft.com]
Sent: Saturday, May 17, 2008 1:54 AM
To: Windows System Software Devs Interest List
Subject: Re:[ntdev] where does Dirty Bit exsist in partition ?

I did a very small amount of digging on google and came up with these. I
can’t vouch for this information, just found it on google.

http://www.withinwindows.com/2007/09/17/setting-ntfs-dirty-bit-without-u
sing-fsutil/
http://technet2.microsoft.com/windowsserver/en/library/3dd141a8-57b8-4bd
8-81dd-69c515fd059f1033.mspx?mfr=true

If your in a volume upper filter for example, I’d take a look at the
IOCTL codes that are passing your way when you run

fsutil dirty query.

Chris

“Tim Roberts” wrote in message news:xxxxx@ntdev…
> xxxxx@gmail.com wrote:
>> When Windows system experienced power off accidently, there will be a

>> disk scan after restarting.
>>
>> MSDN said: when the system started ,it checked out the Direty Bit in
>> partition, the disk scan will begin.
>>
>> ensample:
>> chkntfs C: {This would manually schedule a chkdsk on C: on the next
>> boot - the dirty bit is set for C:}
>
> Why do you want to know? It’s a bit in the master file table (MFT).
> You can’t possibly hope to manipulate this bit manually. You can
> check and set the bit using the “fsutil” utility:
> fsutil dirty query C:
> fsutil dirty set C:
>
> –
> Tim Roberts, xxxxx@probo.com
> Providenza & Boekelheide, Inc.
>
>

—
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6

A fair point, well presented. If you want to see the IOCTL you may have to
play in file system land. However, given that this is (we seem to believe) a
bit in either the MFT or the BOOT sector, at some point the file system
driver is going to write it to the volume. The position and size of the MFT
and the BOOT sector are well known.Given that the exact bit position doesn’t
appear to be avialable perhaps it would be possible to make use of fsutil
and do a bit of before/after sector comparison.

Chris

“Arora,Harish” wrote in message
news:xxxxx@ntdev…
My understanding is that any ioctl that notifies the NTFS driver to mark
the FS dirty should not go down any further to the volume stack.

Harish

-----Original Message-----
From: Chris Hall [mailto:xxxxx@situssoft.com]
Sent: Saturday, May 17, 2008 1:54 AM
To: Windows System Software Devs Interest List
Subject: Re:[ntdev] where does Dirty Bit exsist in partition ?

I did a very small amount of digging on google and came up with these. I
can’t vouch for this information, just found it on google.

http://www.withinwindows.com/2007/09/17/setting-ntfs-dirty-bit-without-u
sing-fsutil/
http://technet2.microsoft.com/windowsserver/en/library/3dd141a8-57b8-4bd
8-81dd-69c515fd059f1033.mspx?mfr=true

If your in a volume upper filter for example, I’d take a look at the
IOCTL codes that are passing your way when you run

fsutil dirty query.

Chris

“Tim Roberts” wrote in message news:xxxxx@ntdev…
> xxxxx@gmail.com wrote:
>> When Windows system experienced power off accidently, there will be a

>> disk scan after restarting.
>>
>> MSDN said: when the system started ,it checked out the Direty Bit in
>> partition, the disk scan will begin.
>>
>> ensample:
>> chkntfs C: {This would manually schedule a chkdsk on C: on the next
>> boot - the dirty bit is set for C:}
>
> Why do you want to know? It’s a bit in the master file table (MFT).
> You can’t possibly hope to manipulate this bit manually. You can
> check and set the bit using the “fsutil” utility:
> fsutil dirty query C:
> fsutil dirty set C:
>
> –
> Tim Roberts, xxxxx@probo.com
> Providenza & Boekelheide, Inc.
>
>

—
NTDEV is sponsored by OSR

For our schedule of WDF, WDM, debugging and other seminars visit:
http://www.osr.com/seminars

To unsubscribe, visit the List Server section of OSR Online at
http://www.osronline.com/page.cfm?name=ListServer