We are using SMTP on the ironport for inbound and outbound mail.   An SMTP route exists for the receiving domain and the Destination is the Mail Server IP, so all SMTP inbound messages route to the Mail Server.  Outbound messages also go through the SMTP address, but the problem is any internal computer can connect (telnet) to the SMTP address send a message.   I'm looking for how to restrict access to SMTP address, so it Only responds to the Mail Server IP but I'm not finding where to config this in the ironport device.   This is an Audit issue I need to get resolved.

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