Difference between pages "Virtual machine" and "SuperFetch"

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= Creating a VM control file from a forensic image =
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{{Expand}}
  
In general, VM software needs both an image and associated control files.
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SuperFetch is a performance enhancement introduced in [[Microsoft]] [[Windows|Windows Vista]] to reduce the time necessary to launch applications. SuperFetch works with the memory manager service in Windows to analyze memory usage patterns over time to determine the optimal memory content for a given user for a date or time of day. This differs from the [[Prefetch]] technique used in Microsoft Windows XP, which preloads data into memory without analyzing usage patterns.
  
There are a number of ways to create the VM control files needed to run an image as a VM instance.  At present, this article primarily provides a series of tools that can create to VMDK VM control files.
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From [http://msdn.microsoft.com/en-us/library/windows/hardware/dn653317(v=vs.85).aspx]: SuperFetch prioritizes the following kinds of pages to remain in memory:
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* Pages of applications that are used most frequently overall.  
== Creating a VMDK file from a forensic image ==
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* Pages of applications that are commonly used when resuming:
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** After extensive hibernation (for example, first thing in the morning).
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** After shorter periods of sleep or hibernation (for example, after lunch).
  
=== By hand ===
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If SuperFetch detects that the system drive is a fast solid-state drive (SSD) (as measured by Windows Experience Index Disk score), then SuperFetch turns off [[ReadyBoot]].
  
VMDK files are simple text files.  They can be created by hand and then the VM run to allow registry values and passwords to be set as needed prior to boot.
 
  
Jimmy Weg has written a series of blog posts that detail the process.  See the list of blog posts under external links below.
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== Configuration ==
  
=== Linux tools as included in SIFT ===
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Because SuperFetch appears to leave a system with no available memory, some users turn it off to create the appearance of having more free memory. The feature can be configured by changing the <tt>HKEY_LOCAL_MACHINE\SYSTEM\CurrentControlSet\Control\Session Manager\Memory Management\PrefetchParameters\EnableSuperfetch</tt> [[Registry]] key [http://www.codinghorror.com/blog/archives/000688.html]. A value of zero disables SuperFetch, one enables it for booting only, two for applications, and three for both applications and boot. This setting can also be changed using the Services console, <tt>services.msc</tt> [http://tiredblogger.wordpress.com/2007/03/27/superfetch-not-so-super-for-gaming/].
  
Via the SIFT workstation (free), use the following steps:
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== File Formats ==
  
1.open a terminal window
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Data for SuperFetch is gathered by the <tt>%SystemRoot%\System32\Sysmain.dll</tt>, part of the Service Host process, <tt>%SystemRoot%\System32\Svchost.exe</tt>, and stored in a series of files in the <tt>%SystemRoot%\Prefetch</tt> directory [http://www.microsoft.com/technet/technetmag/issues/2007/03/VistaKernel/]. These files appear to start with the prefix <tt>Ag</tt> and have a <tt>.db</tt> extension. The format of these files is not fully known, there is available unofficial partial specification [http://blog.rewolf.pl/blog/?p=214] and open source (GPL) dumper for .db files [http://code.google.com/p/rewolf-superfetch-dumper/]. Some information can be gleaned from these files by searching for [[Unicode]] [[strings]] in them.
2.sudo su
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3.mkdir /mnt/ewf1
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4.mount_ewf.py (Encase Image file path) /mnt/ewf1
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5.qemu-img convert /mnt/ewf1/(encase image file name) -O vmdk (give_a_name).vmdk
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=== Paladin 4 ===
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The SuperFetch feature is seeded with some basic usage patterns when the operating system is installed [http://channel9.msdn.com/showpost.aspx?postid=242429].
  
Paladin 4 (free) can create VMDK files for DD and E01 images.
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== See Also ==
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* [[Prefetch]]
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* [[ReadyBoost]]
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* [[ReadyBoot]]
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* [[Windows SuperFetch Format|SuperFetch Format]]
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* [[Windows]]
  
=== Live View ===
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== External Links ==
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* [http://en.wikipedia.org/wiki/Windows_Vista_I/O_technologies#SuperFetch Wikipedia: Windows Vista I/O technologies - SuperFetch]
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* [http://channel9.msdn.com/showpost.aspx?postid=242429 Channel 9 Interview with Michael Fortin of Microsoft on SuperFetch]
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* [http://www.informationweek.com/news/showArticle.jhtml?articleID=196902178 Microsoft Predicts The Future With Vista's SuperFetch] from Information Week
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* [http://jessekornblum.com/presentations/dodcc08-2.pdf DC3 Presentation: My You Look SuperFetching], by Jesse Kornblum
  
[http://liveview.sourceforge.net/ Live View] (opensource) is reported as not reliable, but it does work with some images.
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== Tools ==
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=== Open Source ===
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* [https://code.google.com/p/rewolf-superfetch-dumper/ rewolf-superfetch-dumper]
  
=== VMware Standalone Converter ===
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[[Category:Windows]]
 
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This may be an option.  Reports of success here and what the steps are would be great.
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=== EnCase ===
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use EnCase (Commercial) to mount the E01 image as an emulated disk (you need to have the Physical Disk Emulator (“PDE”) module installed), then VMware to create virtual machine from the emulated physical disk.  Guidance software has a good guide on how to do this in their support portal. 
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Note – EnCase v7 hasn't been proven to support this, just EnCase 6
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=== VFC - Virtual Forensic Computing ===
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VFC (Commercial) is reportedly very good, but troubles with booting Windows 2003 servers have been reported. It's a little pricey ($1350 for a Corp license) but per one user it WORKS the vast majority of the time and the developer provides excellent support.
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== Creating a KVM image ==
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=== From the linux command prompt ===
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kvm -hda myimage.dd
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memory can be set as an option, cd drives can be presented, etc., and there is an option equivalent to the VMware non persistent mode.
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Warning: It has been determined that using kvm's non-persistent mode can still result in an altered image. Always, always, always work from a copy.
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= Using the VMDK file =
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Once you have the VMDK file, you can create a virtual machine in
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Virtualbox or VMware Workstation and use the VMDK as an existing hard
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disk for the virtual machine. I prefer to use VMware Workstation
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because it has a non persistent mode which allows you to write changes
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to a cache file rather than the forensic image itself thus maintaining
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integrity.
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= External Links =
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* [http://www.myfixlog.com/fix.php?fid=35 How to Create a Virtual Machine from a Raw Hard Drive Image]
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* [http://cyb3rdaw6.harpermountain.net/2011/06/12/get-from-e01-to-live-virtual-machine-with-no-image-conversion/ Get from e01 to live virtual machine with no image conversion]
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== Jimmy Weg's blog ==
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Jimmy Weg has talked extensively about using VM with forensic images on his blog.  These are detailed tutorials that manually create the VMDK file!
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* [http://justaskweg.com/?p=7 Creating a VMware Virtual Machine from a Raw Image File]
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* [http://justaskweg.com/?p=653 Creating a VM from E01 Images]
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* [http://justaskweg.com/?p=851 What About an XP VM?]
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* [http://justaskweg.com/?p=999 How Do I Handle Really* Big Disks?]
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* [http://justaskweg.com/?p=1024 Mounted Images – Breaking the 2TB Barrier]
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Revision as of 01:48, 24 April 2014

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Please help to improve this article by expanding it.
Further information might be found on the discussion page.

SuperFetch is a performance enhancement introduced in Microsoft Windows Vista to reduce the time necessary to launch applications. SuperFetch works with the memory manager service in Windows to analyze memory usage patterns over time to determine the optimal memory content for a given user for a date or time of day. This differs from the Prefetch technique used in Microsoft Windows XP, which preloads data into memory without analyzing usage patterns.

From [1]: SuperFetch prioritizes the following kinds of pages to remain in memory:

  • Pages of applications that are used most frequently overall.
  • Pages of applications that are commonly used when resuming:
    • After extensive hibernation (for example, first thing in the morning).
    • After shorter periods of sleep or hibernation (for example, after lunch).

If SuperFetch detects that the system drive is a fast solid-state drive (SSD) (as measured by Windows Experience Index Disk score), then SuperFetch turns off ReadyBoot.


Configuration

Because SuperFetch appears to leave a system with no available memory, some users turn it off to create the appearance of having more free memory. The feature can be configured by changing the HKEY_LOCAL_MACHINE\SYSTEM\CurrentControlSet\Control\Session Manager\Memory Management\PrefetchParameters\EnableSuperfetch Registry key [2]. A value of zero disables SuperFetch, one enables it for booting only, two for applications, and three for both applications and boot. This setting can also be changed using the Services console, services.msc [3].

File Formats

Data for SuperFetch is gathered by the %SystemRoot%\System32\Sysmain.dll, part of the Service Host process, %SystemRoot%\System32\Svchost.exe, and stored in a series of files in the %SystemRoot%\Prefetch directory [4]. These files appear to start with the prefix Ag and have a .db extension. The format of these files is not fully known, there is available unofficial partial specification [5] and open source (GPL) dumper for .db files [6]. Some information can be gleaned from these files by searching for Unicode strings in them.

The SuperFetch feature is seeded with some basic usage patterns when the operating system is installed [7].

See Also

External Links

Tools

Open Source