Before configuring the Mail Gateway service, you must create it. For more information, see How to Configure Services. You must also have a server installed on the Barracuda NextGen Firewall F-Series.
Configure the basic mail gateway settings
- Go to CONFIGURATION > Configuration Tree > Box > Virtual Servers > your virtual server > Assigned Services > Mail-Gateway > Mail Gateway Settings.
- Click Lock.
- On the MailGW Settings - Basic Setup page, configure the host, local domain, and global domain settings. For more information on these settings, see the following Basic Mail Gateway Settings section.
- Click Send Changes and Activate.
For your server, configure more than one bind IP address that is reverse DNS resolvable. Otherwise, the mail gateway may not function correctly and the "Cannot bind to IP" error message displays in the system logs.
The server uses the standard SMTP port 25 and the listen IP addresses to listen for requests. An inbound and outbound mail gateway must have at least two listening IP addresses. Inbound and outbound mail traffic are identified by the following listening IP types:
- Internal – Usually connects your LAN clients. If you are operating a mail server in your internal LAN, you can specify the mail gateway's internal listening IP address as a mail relaying address. If you do not have a dedicated mail server, clients may specify the gateway's internal listening IP address as an outgoing SMTP server address in the configuration of their email client programs.
- External – Connects your LAN to an external network.
The mail gateway determines the transportation direction by the email's incoming IP address. Mail rules are only interpretable when internal and external listening IPs are configured properly.
In the Host Configuration section, edit the following settings to specify your listen IP addresses and the email address of the postmaster:
External Listen Address |
In the External Listen Address and Internal Listen Address tables, add the listen IP addresses for the mail gateway. When adding a new IP address, specify the following settings:
|Postmaster Mail-Address||The email address of the postmaster.|
Local Domain Settings
In this section, specify the mail server and trusted domains.
|Internal Mail Server|
The internal mail server. The mail gateway redirects incoming mail to this server.
|My Domains List|
In this table, add domains that are trusted by the mail gateway. The mail gateway will only accept mail relaying for these domains on its listening IP addresses.
When adding a domain, specify the following settings:
Global Domain Parameters
In this section, specify the database, authentication scheme, and group patterns for recipient verification. You can also specify email relay hosts.
|Default Recipient DB|
The relative path and name of the default database for recipient verification. If the configured server is unreachable or does not respond with the mail attribute, the email is not accepted.
|Default Recipients||Click Ex/Import to export or import recipients in the default recipient database.|
|Default Recipients Lookup|
The authentication scheme used for an online mail recipient lookup in a meta directory for incoming mail. You can disable this setting, or you can select either MSAD or LDAP.
The recipient email address is checked against the meta directory attribute named mail. If the meta directory server is unreachable or does not reply with the mail attribute, the email is not accepted.
|Recipients Lookup req. Groups|
The group patterns that must be matched by the recipient.
|Allow Relaying from|
The hosts that are allowed to forward emails to be relayed on the internal listen IP address.