It is difficult to tell from the information provided but a mail loop is detected by SMG when the connecting IP is either an IP that is configured on the SMG OR an IP address of SMG is one IP address prior to the connecting IP address.
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Strategic Support Engineer
Broadcom
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Original Message:
Sent: 07-03-2020 07:22 AM
From: Jacqueline Nuque
Subject: Mail Loop in SMG
Hi All,
Hope everyone is doing well.
Our customer is currently migrating from LN to O365 and currently undergoing end-to-end tests. Just this morning, they received some test email coming from o365connectorvalidation@customer.domain. However, emails coming from one test user who is now on-board O365 return mail loop status on our SMG. What could be causing the mail loop?