In Symantec DLP version 10 there is a possibility to preform the action you are requiring. It is called "inventory scanning". You can create a Threshold in which after X incidents the system would go on to the next server/scanning target.
Here is a snapshot:

Here is the description in the documentation (Page 302 in the DLP Administration Guide):
"Inventory Scanning Enter the number of incidents to produce before moving on to the next item to scan (a file share fromthe ScannedContent tab). To audit whether confidential data exists on a target, without scanning all of it, set up Inventory Mode for scanning. Setting incident thresholds can improve the performance of scanning by skipping to the next item to scan, rather than scanning everything.
After the incident threshold has been reached, the scanning of this item is stopped, and scanning proceeds to the next item. Because the process is asynchronous, a few more incidents may be created than specified in the incident threshold.
Select Content Root (the default), or Machine.
The content root is one file share on the list from the Scanned Content tab.
When the incident threshold is reached, the scan moves to the next file share.
Select the Machine option to count by physical computer (from the specified shares on a computer).
When the incident threshold is reached, the scan moves to the next item on the list to scan. If that item is on the same physical computer as the previous item, it is skipped.
Note that the physical computer name must be literally the same, for the
item to be skipped. For example, \\localhost\myfiles and
\\127.0.0.1\myfiles are treated as different computers, even though
they are logically the same."
I have checked and this feature exists in Symantec DLP Version 9.1 as well, I do not know about older versions.
Kind Regards,
Naor Penso