By default Trellix DLP Network Prevent – SaaS accepts messages from any host. Specify the hosts that can send messages to Trellix DLP Network Prevent – SaaS so that only legitimate source MTAs can relay email though the appliance.
Specify the Smart Hosts that can send messages.
In ePO - SaaS, 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 Permitted Hosts, select Accept mail from these hosts only.
Type the details of a host that Trellix DLP Network Prevent – SaaS can receive messages from.
Add the host information using its IP address and subnet, domain names, or wildcard domain name.
Click Update to add the details to the list of permitted hosts.
You can create groups of relay hosts using subnets or wildcard domains. To add more than one subnet, you must create separate entries for each.
Click Save.