Windows Server 2008 R2 Glossary - D

Updated: June 10, 2009

Applies To: Windows Server 2008 R2

For more Windows Server terms, see either the Windows Server 2008 Glossary or the Windows Server 2003 Glossary

Glossary - D

# A B C D E F G H I J K L M N O P Q R S T U V W X Y Z

differencing virtual hard disk

A virtual hard disk that stores the changes or "differences" to an associated parent virtual hard disk for the purpose of keeping the parent intact. The differencing disk is a separate .vhd file that is associated with the .vhd file of the parent disk. Changes continue to accumulate in the differencing disk until it is merged to the parent disk.

dot source

In Windows PowerShell, to start a command by typing a dot and a space before the command. Commands that are dot sourced run in the current scope instead of in a new scope. Any variables, aliases, functions, or drives that command creates are created in the current scope and are available to users when the command is completed.

dynamically expanding virtual hard disk

A virtual hard disk that grows in size each time it is modified. This type of virtual hard disk starts as a 3 KB .vhd file and can grow as large as the maximum size specified when the file was created. The only way to reduce the file size is to zero out the deleted data and then compact the virtual hard disk.