Server mode deployment
The following procedures and examples show you how to deploy the FortiMail unit in server mode.
- Configuring DNS records
- Example 1: FortiMail unit behind a firewall
- Example 2: FortiMail unit in front of a firewall
- Example 3: FortiMail unit in DMZ
Configuring DNS records
You must configure public DNS records for the protected domains and for the FortiMail unit itself.
For performance reasons, you may also want to provide a private DNS server for use exclusively by the FortiMail unit.
This section includes the following:
- Configuring DNS records for protected domains
- Configuring DNS records for the FortiMail unit itself
- Configuring a private DNS server
Configuring DNS records for protected domains
Regardless of your private network topology, in order for external MTAs to deliver email to the FortiMail unit, you must configure the public MX record for each protected domain to indicate that the FortiMail unit is its email server.
For example, if the fully qualified domain name (FQDN) of the FortiMail unit is fortimail.example.com, and example.com is a protected domain, the MX record for example.com would be:
example.com IN MX 10 fortimail.example.com
If your FortiMail unit will operate in server mode, configure the MX record to refer to the FortiMail unit, and remove other MX records. If you fail to do so, external MTAs may not be able to deliver email to or through the FortiMail unit, or may be able to bypass the FortiMail unit by using the other MX records. If you have configured secondary MX records for failover reasons, consider configuring FortiMail high availability (HA) instead. For details, see “FortiMail high availability modes” on page 23.
An A record must also exist to resolve the domain name of the FortiMail unit into an IP address.
For example, if the MX record indicates that fortimail.example.com is the email gateway for a domain, you must also configure an A record in the example.com zone file to resolve fortimail.example.com into a public IP address: fortimail IN A 10.10.10.1
where 10.10.10.1 is either the public IP address of the FortiMail unit, or a virtual IP address on a firewall or router that maps to the private IP address of the FortiMail unit.
If your FortiMail unit will relay outgoing email, you should also configure the public reverse DNS record. The public IP address of the FortiMail unit, or the virtual IP address on a firewall or router that maps to the private IP address of the FortiMail unit, should be globally resolvable into the FortiMail unit’s FQDN. If it is not, reverse DNS lookups by external SMTP servers will fail.
For example, if the public network IP address of the FortiMail unit is 10.10.10.1, a public DNS server’s reverse DNS zone file for the 10.10.10.0/24 subnet might contain:
1 IN PTR fortimail.example.com.
where fortimail.example.com is the FQDN of the FortiMail unit.
Configuring DNS records for the FortiMail unit itself
In addition to that of protected domains, the FortiMail unit must be able to receive web connections, and send and receive email, for its own domain name. Dependent features include:
- delivery status notification (DSN) email
- spam reports
- email users’ access to their per-recipient quarantines
- FortiMail administrators’ access to the web UI by domain name
- alert email
- report generation notification email
For this reason, you should also configure public DNS records for the FortiMail unit itself.
Appropriate records vary by whether or not Web release host name/IP (located in AntiSpam > Quarantine > Quarantine Report in the advanced mode of the web UI) is configured:
- Case 1: Web Release Host Name/IP is empty/default
- Case 2: Web Release Host Name/IP is configured
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