Trellix DLP Network Prevent delivers email messages using the configured Smart Host. You can add more MTAs that Trellix DLP Network Prevent deliver email messages in addition to the Smart Host.
Make sure that you have the IP addresses or host names of the Smart Hosts.
Trellix DLP Network Prevent accepts email messages from more than one MTA, but forwards the inspected email messages to only one of the configured Smart Hosts.
In ePO - On-prem, open the Policy Catalog.
Select the DLP Appliance Management product, choose the Trellix DLP Network Prevent Email Settings category, and open the policy that you want to edit.
In the Smart Hosts field, add the details of the MTAs that you want to use.
Click Update and click Save.