Identify IP addresses that you can use to accept emails coming only from HES servers. If you prefer the network to receive emails from HES IP address ranges only, you have to whitelist these HES IP address ranges for incoming SMTP rules on the network firewall.
This can be used in a scenario wherein you prefer all emails to go through HES first, and exclusively allow HES to send SMTP traffic to your network.
To receive emails coming only from HES servers, configure the firewall to accept emails only from the following IP addresses:
For EMEA site:
For all other regions:
Additionally, if your firewall, MTA, or mail server is configured to check any IP Reputation / RBL service provider, the same set of IP blocks above must be added to the IP Reputation approved list. Another option is to disable the IP Reputation checking on the firewall, MTA, or mail server and let HES handle this task.
Should you need assistance regarding your firewall, contact your network administrator.