NTFS Collections Miscellaneous Information

Article:TECH56891  |  Created: 2008-01-18  |  Updated: 2012-03-26  |  Article URL http://www.symantec.com/docs/TECH56891
Article Type
Technical Solution

Product(s)

Environment

Issue



NTFS Collections Miscellaneous Information


Solution



Note: For information on configuring NTFS Collections, please see the Related Documents section below.

 
  • By placing the numerous small files into fewer large files, collections will reduce the backup window required for backing up the Vault Store partitions.

 
  • The CAB files are created in the "Day" folder in the vault store location (YYYY\MM\DD).

 
  • The default maximum collection size has been reduced from 200 MB to 10 MB. Increasing this value when collection files verification is on has a significant performance impact. The permissible range for the maximum CAB file size is now 1-99 MB; previously this was 1-999 MB.

 
  • When collection files are used on NTFS volumes or network share partitions, Enterprise Vault automatically verifies the contents of each collection file when it has been created. This ensures that there is no corruption of the file. Because of the performance impact of this change, the following registry key may be set to turn off collection file validation:

 
HKEY_LOCAL_MACHINE\SOFTWARE\KVS\Enterprise Vault\Storage
 
DWORD value: VerifyCollectedFiles
 
Value data: 0
 

 
  • The collection process is fairly lightweight and normally runs during the day. Items are collected at approximately twice the rate at which they are archived, so you should be able to estimate the time required for collections to complete based on your archiving.

 
  • The size of the CAB file is the determining factor when it comes to the user experiencing any additional delay when a DVS file gets extracted from a CAB.

 
  • Once an archived item is in a CAB, subsequent archived copies of it are not shared, which reduces the single instancing of an item. So, it's important to ensure that items are not collected too early otherwise this will reduce single instance storage efficiency.

 
  • Collections can increase the time it takes to rebuild/update a failed index.

 
  • When running expiry to delete items from the vault, collected items stay in the CAB thus consuming disk space until there are less than 15 (by default) 'active' items in the collection at which point they become DVS files again. Each CAB may contain up to 1000 DVS files.

 
  • There are no additional disk space savings as the DVS files are already compressed. There is no additional compression when stored as a CAB.

 
  • Once collections are "turned on" for a Vault Store partition, it cannot be "turned off". To discontinue the use of collections, you will need to open a new Vault Store Partition. To extract the DVS files from the CAB files, a utility named uncollect.exe must be utilized.

 
  • When the user opens a shortcut, the DVS file is extracted to the Vault Service Account profile temp directory on the Enterprise Vault server before being copied back into the original location in the Vault Store partition. If the temp directory is inaccessible or the disk is near full then the operation will fail. It is also important to prevent any antivirus software from scanning the temp directory.

 
  • When a request is made to an archived item that is collected into in a CAB file, EV extracts the DVS file out of the CAB with an ARCHDVS file extension.  The ARCHDVS files are automatically removed from the partition by the collection process during its next scheduled run if the Last Accessed time is greater than 24 hours.



Legacy ID



296240


Article URL http://www.symantec.com/docs/TECH56891


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