NetBackup Causing Windows Low Disk Space

Story of Low Disk Space:

You have bought a new setup which is having 1 master and 100 more clients. All VERITAS and tape library configurations were done. With a big gulp of air you are initiating full backup for all clients and a green dressed running man initiated all client backups.

Backup is in progress for all clients without any issues and some jobs completed with status code 0 and 1. In some time all backup jobs get completed and you cross verified for the list of clients that completed with 1 and 0.

You are running backup in daily manner without any issues. Unexpectedly your Project and Windows admin guys saying that “we are running out of space in some servers and we cross verified everything, all seems normal; except one folder that located in all servers Drive named “NBU_CACHE” and its eating server’s space in GB’s“; You are getting into that issue and found that It have a hidden file and that did matter.

Project and Windows Admin guys forcing you to solve this soon as some servers are standing with out space in OS Drive too.

You have got a good knowledge in googling; you dig in Google and found a Net Backup document (VERITAS Administrator Guide 1).

You got to know the following details: 

  • Veritas Open files Backup methodology.
  • VERITAS uses 2 types of snapshots providers
  • Veritas Snapshot Provider
  • Volume Shadow Copy Service.
  • By default Veritas enables open file backup with VSP as a Snapshot provider.
  • VSP can be used for Windows XP, 2000,2003 and its developed by Veritas
  • VSS can be sued for Windows 2003 and higher versions and it’s developed by Microsoft.      

And also you found that VSP Snapshot will be automatically deleted once backup is completed and there you got a big doubt.

You don’t understand why the VSP not deleted automatically, so you are again contacting your master blasterGOOGLE for this. Now you got one Symantec technical document saying “Large files named "_vxfiVspCacheFile_x.tmp" or "_vxfiVspCacheFile_x.vsp" are appearing in the root directory of clients and cannot be deleted”,with much more interest you are reading that document.

After a long read, you are getting some ideas related to the issue;

Antivirus is blocking Veritas from deletion of file

An exact scenario that was mentioned in the document is “Antivirus will scan for Virus whenever a file got created or modified, Whenever VSP creates Snapshot, Antivirus will start scanning that file to check for harmful virus; and once the backup is over Veritas will inform the client that backup is completed and just go ahead and delete the Snapshot, but When Client tries to delete that Snapshot file and operation got failed because of Anti Virus scan. So Snapshot is not deleted and it will occupy space in server as long.

And resolution as by excluding the NBU_Cache folder in Anti Virus Scan.

You got very happy by knowing this information’s but your mind voice forced you to contact Symantec Technical Support.

Then, you have raised a request with Symantec Technical support and your good time you got immediate response from Support.

Symantec support guy stared collecting the information about your setup, after a full study, he begin the case with some instructions.

VSP is a snapshot provider technology that was introduced by VERITAS since the days of WinNT. However with Windows 2003 we now have the Microsoft VSS which does the same job as VSP. You can configure Netbackup to use VSS instead of VSP for windows 2003 clients and for older clients you can configure VSP by excluding some files. Doing this will minimize the errors or conflicts with the Antivirus application.

Listed below is the compilation of best practices specific to VSP and VSS

 >> How to ensure that the Antivirus application does not interfere with the VSP snapshot creation process?

  • Exclude the file called _vxfiVspCacheFile_*.* (VSP cache files will either have a .tmp or .vsp extension, depending upon the version of NetBackup, but will always contain "_vxfiVspCacheFile_" in the name, followed by a number.)
  • Exclude the following NetBackup executables on the client machine: 
  • The screenshot below shows how to configure NBU to use MS VSS instead of the default Veritas (VSP). (NBU client service needs to be restarted on that server after making any changes)imagebrowser imageimagebrowser image

>> How to remove the snapshot that is created in client drives?

>> How can you ensure that VSP is not installed during a fresh install of Netbackup client on a new Win2K3 server?

  • Simply choose the Custom Install method and choose not to install the VSP driver.

>> How to remove VSP from an existing Win2K3 server that already has the Netbackup client installed?

  • Un-install the Netbackup client completely.
  • Reboot.
  • Ensure VSP Kernel driver is no longer on the system. Start >> Run >> msinfo32 >> Software Environment >> Look for VSP in the list.
  • Do a clean install of Netbackup client v6.5 (Custom Install method)
  • Install the latest maintenance pack

 >> How to remove VSP in a clustered environment.

  • Remove it from the active node. Failover to the second node and do the same.

 >> How to configure the cache file size when using Microsoft VSS?

(The following has been sourced from Symantec Technote …

  • In Windows, right-click My Computer and select Manage
  • In the console tree, right-click Shared Folders, select All Tasks, and then Configure Shadow Copies
  • Select the volume on which to make changes, and then click the Settings button
  • In the Settings dialog box, change the Maximum Size setting to either No Limit or a size large enough to suit the requirements of the installation and usage of VSS
  • You may even dedicate a separate drive exclusively for VSS cache file usage. This improves performance and reliability of backup jobs.

>> Some important links