Windows IT Pro is the leading independent community for IT professionals deploying Microsoft Windows server and client applications and technologies.
  
  
  Advanced Search 


November 2000

Exploring NTFS On-disk Structures


RSS
Subscribe to Windows IT Pro | See More Storage Articles Here | Reprints | Or get the Monthly Online Pass—only $5.95 a month!
Main Article    Inside Win2K NTFS, Part 1

Few publicly available tools let you explore the internals of the NTFS on-disk structure. One of those few is DiskEdit, an internal NTFS testing tool that Microsoft inadvertently shipped on the Windows NT 4.0 Service Pack 4 (SP4) CD-ROM and the most powerful NTFS viewer I've seen. DiskEdit, which Figure A shows, provides a detailed look at the structures that make up files and directories, translates file and directory paths to Master File Table (MFT) entry numbers, and lets you look at attribute data. No documentation accompanies DiskEdit, but I provide a tutorial for it in a back issue of my free Sysinternals Newsletter (http://www.sysinternals.com/newsletter.htm). To use DiskEdit on Windows 2000, you must copy the ifsutil.dll, ulib.dll, untfs.dll, and ufat.dll files from an NT 4.0 system's \winnt\system32 directory to the directory from which you want to run DiskEdit.

If you're interested in NTFS data structure information but can't get your hands on an SP4 CD-ROM, you can use NFI, the NTFS File Sector Information Utility, which Microsoft includes with its OEM Support Tools package at http://support.microsoft.com/support/kb/articles/ q253/0/66.asp. (In addition to NFI, the OEM Support Tools include debugging utilities and kernel debugger extensions to help support personnel and developers analyze crash dumps.)

NFI accepts several command-line forms that let you dump information about a particular file or directory or about all the files on a volume, obtain the file or directory in which a particular logical sector on a drive resides, or obtain the file or directory in which a particular physical disk sector resides. For example, the command

nfi C: 123

reports the name of the file on volume C: that contains the volume's 123rd sector. To examine NTFS data structures, you can use the same command but omit the sector number to tell NFI to dump detailed information about attributes in all the disk's files. You can specify the name of the metadata files I describe in the column to view evidence of the index attributes they contain. For example, executing the command

nfi c:\$extend\$quota

on a volume that has quota management enabled results in output that shows that the $Quota file contains indexes named $O and $Q:

File 24
\$Extend\$Quota
$STANDARD_INFORMATION (resident)
$FILE_NAME (resident)
$INDEX_ROOT $O (resident)
$INDEX_ROOT $Q (resident)

For another source of NTFS on-disk structure information, see Gary Nebbett, Windows NT/2000 Native API Reference (New Riders Publishing, 2000). An appendix lists the definitions for many NTFS on-disk data structures (some of which don't reflect changes in Win2K) and contains the source code for a Win32 program that interprets the data structures to bypass the NTFS file-system driver and dump a volume's contents.

End of Article



Reader Comments

You must be a registered user or online subscriber to comment on this article. Please log on before posting a comment. Are you a new visitor? Register now




Top Viewed ArticlesView all articles
Command Prompt Tricks

One reader shares his tip for setting up the command prompt to reflect a remote path. ...

WinInfo Short Takes: Week of November 9, 2009

An often irreverent look at some of the week's other news, including some more Windows 7 sales momentum, some Sophos stupidity, Microsoft's cloud computing self-loathing, more whining from the browser makers, Zoho's "Fake Office," and much, much more ...

Understanding File-Size Limits on NTFS and FAT

A general confusion about files sizes on FAT seems to stem from FAT32's file-size limit of 4GB and partition-size limit of 2TB. ...


Storage Whitepapers Turn to a Proven Server and Storage Migration Solution

The Impact of Disk Fragmentation on Servers

Take Control of Your Email: Understand the Business Reasons for Email Storage Management

Related Events Disk-to-Disk Grows Up

WinConnections and Microsoft® Exchange Connections

Deep Dive into Windows Server 2008 R2 presented by John Savill

Check out our list of Free Email Newsletters!

Storage eBooks A Guide to Windows Certification and Public Keys

SQL Server Administration for Oracle DBAs

Keeping Your Business Safe from Attack: Encryption and Certificate Services

Related Storage Resources Introducing Left-Brain.com, the online IT bookstore
Looking for books, CDs, toolkits, eBooks? Prime your mind at Left-Brain.com

Discover Windows IT Pro eLearning Series!
Clear & detailed technical information and helpful how-to's, all in our trademark no-nonsense format


Windows IT Pro Home Register FAQ for Windows WinInfo News
Europe Edition About Us Contact Us/Customer Service Media Kit Affiliates / Licensing  
SQL Server Magazine Office & SharePoint Pro DevProConnections IT Job Hound
Left-Brain.com Technology Resource Directory asp.netPRO ITTV Windows SuperSite 
 
 Windows IT Pro is a Division of Penton Media Inc.
 © 2009 Penton Media, Inc. Terms of Use | Privacy Statement