Deployment and Initial Configuration
The Deployment and Initial Configuration domain tests whether you can choose the right FortiMail operating mode and build a working base configuration: interfaces, DNS, administrator access, mail domains, and the first policies. Expect scenario questions about gateway versus transparent versus server mode, and about which settings must exist before mail flows.
Operating modes
- Gateway mode places FortiMail behind the firewall as an SMTP relay. It scans inbound mail and relays to an internal mail server; outbound mail can also relay through it. It is not a mailbox server.
- Transparent mode inserts FortiMail as a bridge inline with an existing mail server, usually without changing MX records or IP addresses. A management IP is still required.
- Server mode makes FortiMail the mail server, with local domains, mailboxes, POP3/IMAP, and webmail. Changing mode is disruptive; plan it before production and expect a reboot or service restart.
Base configuration checklist
- Set a unique FQDN hostname and correct DNS A, MX, and PTR records. A mismatched PTR or HELO name hurts deliverability and can trigger rejections.
- Configure interfaces, default gateway, NTP, and administrative access. Restrict admin protocols and use trusted hosts.
- Register and license the unit and verify FortiGuard connectivity for antivirus and antispam updates.
- Define mail domains: local domains for server mode; protected or relay domains for gateway and transparent mode.
- Configure a relay host or destination server if outbound mail must use a smart host.
- Create administrator profiles with least privilege, then take a configuration backup.
Worked example
A company keeps Exchange and wants inline scanning without changing MX records. The correct choice is transparent mode: place FortiMail in bridge mode between the firewall and Exchange, give it a management IP, define the protected domain, and let SMTP pass through. Gateway mode would also work but requires MX or firewall changes; server mode would add mailboxes that are not needed. The reasoning is that transparent mode preserves the existing mail flow and IP addressing while still allowing scanning.
Traps
- Assuming gateway mode provides local mailboxes.
- Forgetting PTR and HELO alignment, then blaming antispam.
- Leaving admin access open to all interfaces.
- Changing the operating mode after policies and domains exist without retesting mail flow.