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Capturing email messages as events

ZenMail and ZenPop3 can capture email messages as events. This capability can be useful for situations in which embedded systems (such as WAPs, NAS devices, or RAID controllers) rely on email notification for events.


ZenMail serves as an SMTP server that you can bind to a specific TCP port. You can then configure your embedded system to send mail to the Collection Zone server explicitly by using the server's IP address as the relay.

ZenMail supports two configuration alternatives:

  • Bind to port 25 on all ports and listens for email messages to arrive (default). Ignore the TO field in the email and use the FROM address as the device IP address.
  • Bind to a specific port. Useful in situations in which an SMTP server is already running on the Collection Zone server and you do not want to interfere with the existing mail delivery system. Semantics are the same as the no argument version (FROM address is used as the device IP).


ZenPop3 allows you to retrieve event email from a POP server. ZenPop3 supports these configuration directives:

Directive Description

Issue the STARTTLS command to the POP server and attempt to transfer email messages using SSL encryption.

This is required if retrieving mail from Google.


Do not issue the DELE command after retrieving all messages. Typically this is used during initial testing so that you do not have to resend test messages to the POP account.

Some email systems (such as Google) do not actually delete messages when the DELE command is issued.

--pophost The hostname or IP address of the POP server from which to retrieve messages.

The TCP port the POP server listens on. Defaults to 110.

Used in situations where the POP provider listens on another port (for example, Google on port 995).

--popuser The user name that contains email messages to retrieve.
--poppass The password to use for the user name provided.

The time to sleep between polls.

After all email is retrieved, ZenPop3 sleeps for this amount of time before waking up and attempting to pull new email.

Translating message elements to the event

Collection Zone translates various message elements to the event, as follows:

Field Description
FROM If the FROM field is an IP address, then the system associates the event with the device with the same IP address. If the FROM field is a fully qualified domain name, then the system resolves it to an IP address, and then performs the device association using the resolved IP address. The resolution of hostname uses "A" records rather than "MX" records.
TO The system ignores the TO field in the email message. ZenMail accepts email to any user and domain name combination. ZenPop also drops the TO field, and uses only the FROM field.
SUBJECT ZenMail and ZenPop use the SUBJECT as the event summary.
Message body ZenMail and ZenPop use the first mime attachment as the event details. The system ignores secondary message bodies (typically HTML-encoded versions of the message). It also ignores attachments (such as files).