When trying to export the total number of agents that a DLP system has in DLP to a file from the Agent Summary Report in the Enforce console the default limit is set 30000.
This is a limit that is set in a configuration file. You can modify this file to get your agents exported but please be careful as this can impact performance and such if you are running with limited resources on the server.
Steps to be used on Enforce Server
Default Locations (Substitute your DLP version):
Windows: C:\Program Files\Symantec\DataLossPrevention\EnforceServer\[DLP Version]\Protect\config\manager.properties
Linux: /opt/Symantec/DataLossPrevention/EnforceServer/[DLP Version]/Protect/config/manager.properties
Note: Please be sure to create a backup of the Manger.properties file before making any edits in case you need to roll back.