Windows 2008: Difference between revisions

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(→‎Build: Added ASLR)
(→‎Disable ASLR: Updated with argument for and against)
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=== Disable ASLR ===
=== Disable ASLR ===
Address space layout randomisation is a feature which involves randomly arranging the positions of key data areas, in order to mitigate memory snapshot image vulnerabilities (which is generally not a problem).  This can reduce reduce VMware's page sharing between VM's, increasing overall physical memory usage.
Address space layout randomisation is a feature which involves randomly arranging the positions of key data areas, in order to mitigate memory snapshot image vulnerabilities (which is generally not a problem).  There are suggestions that this can reduce reduce VMware's page sharing between VM's, increasing overall physical memory usage.  However, its probably true that whilst memory page locations will be randomised, the VMkernel will still be able to match up identical pages between different OS instances.


  HKLM\SYSTEM\CurrentControlSet\Control\Session Manager\Memory Management\"MoveImages"=dword:00000000
  HKLM\SYSTEM\CurrentControlSet\Control\Session Manager\Memory Management\"MoveImages"=dword:00000000

Revision as of 11:42, 22 November 2010

Build

Best practice for VMs (take with a pinch of salt)

Disable ASLR

Address space layout randomisation is a feature which involves randomly arranging the positions of key data areas, in order to mitigate memory snapshot image vulnerabilities (which is generally not a problem). There are suggestions that this can reduce reduce VMware's page sharing between VM's, increasing overall physical memory usage. However, its probably true that whilst memory page locations will be randomised, the VMkernel will still be able to match up identical pages between different OS instances.

HKLM\SYSTEM\CurrentControlSet\Control\Session Manager\Memory Management\"MoveImages"=dword:00000000

Procedures

Sysprep

  1. Start sysprep from C:\Windows\System32\sysprep\sysprep.exe
  2. Leave action as Enter System Out-of-Box Experience (OOBE) and tick the poorly spelt Generalize tick-box, then hit OK
  3. Sysprep will run and reboot the OS
    • You'll need to provide a new password, and any hostname and IP details will need updating

Troubleshooting

Default Gateway Loss

Known bug in Windows 2008 SP2 causes the default gateway of a machine to disappear on reboot. Resolved by resetting the IP stack and re-entering the IP config

  1. Record IP details
    • ipconfig/all > C:\ipconfig.txt
  2. Reset the IP stack
    • netsh int ip reset
  3. Restart server
  4. Re-enter IP config
  5. Reboot to confirm its held

There's a bugfix available from http://support.microsoft.com/kb/973243

Scheduled Tasks

Error 2147943712 You're trying to save a task that wants to save credentials (maybe because you want the task to run even when the user is logged off), but credential saving has been disabled by a GPO.