Misconception One: SMTP message origination
One of the common misconceptions with architects is in regards to properly defining the source of SMTP messages. As an architect, it is important to know that SMTP messages are sent (when configured to do so) within Schedules are Workflows. For example, if the Identity Panel customer needs to see a weekly report of department changes, sent to them via email, the customer needs SMTP.
The misconception among architects is that messages originate from the Identity Panel Web Application Service hosted on premise, in OneDesign, or from the Azure Marketplace when using SaaS. This is not the case. All SMTP message are sent to the SMTP relay server from the Identity Panel Windows Service (Panel Service) regardless of the Identity Panel edition in use.
Because messages are sent from the Panel Service hosted on premise, Identity Panel Web Application Service does not send the message. Therefore, you must have an SMTP relay host that Identity Panel can use to relay messages.
Misconception Two: Only one Panel Service sends messages
This misconception is more of a mistake from the evolving deployment birthed when a installation starts with a single Panel Service. At many customer locations, we see Panel Service typically installed on a MIM Synchronization server. Months later, comes a second Panel Service installation on the ADConnect server, and then the ADFS server, and so on. When these additional services are added, it is common to overlook each new Panel Service's needs to also send SMTP messages.
A good design and deployment will have every Panel Services capable of sending SMTP messages. This is because a single Panel Service does not act as the SMTP gateway, but rather, each Panel Service sends messages for the Workflow or Schedule the respective Panel Service is running, when message services are required. It is the Workflow or Scheduler that choose in its definition by the administrator, what Panel Service or Panel Service Pool that will execute the Workflow or Schedule, and therefore, will also be the Panel Service or Panel Service Pool the is responsible for sending any messages for the Workflow or Schedule, to the SMTP relay.
For more information, see Setting up SMTP for Identity Panel
Posted to Twitter @IdentityPanelKB on June 12, 2017