Shares on file servers become temporarily unresponsive.

Problem

End users may experience temporary unresponsiveness of shares that are targeted for File System Archiving. This unresponsiveness will result in the inability to browse or manipulate the file system for a period of time. The period of unresponsiveness will vary and may last several minutes. Once the unresponsiveness has ended access to the shares will return to normal. It is important to note that the server itself will be responsive from the console, but the file shares will remain unresponsive when accessing via windows explorer.

Error Message

There are no error messages presented to the user. However, the main symptom will be unresponsive file shares.

Cause

The cause of this issue appears to be related to the filter holding all the Kernel allocated SMB threads while downloading a large file. As there is only a finite number of SMB threads spawned, based on system resources,  large file or excessive recalls which take longer to retrieve cause the file shares to be unresponsive. 

Workaround

To work around the issue during a period of extended unresponsiveness unload the evfilter mini-filter driver,  reload the evfilter mini-filter driver, and restart the placeholder service. At this point file share responsiveness will be restored.
 
 To unload and load the evfilter mini-filter driver:
 
From an administrator command prompt on the file server type the following:
 
To Unload:
fltmc unload evfilter
 
To Load:
fltmc load evfilter
 
Restart the Enterprise Vault File Placeholder Service

Solution

This issue has been addressed in the following releases:

Enterprise Vault 12.2.1
https://www.veritas.com/docs/100034312

Enterprise Vault 12.3
https://www.veritas.com/docs/100041266

JIRA : CFT-70 Etrack : 3902063