Technical Tip: FortiMail LDAP-based mail routing

[nagarajs_FTNT]

Description	This article describes guidance on configuring LDAP-based Mail routing in FortiMail.
Scope	FortiMail.
Solution	When an email is accepted, FortiMail can query the LDAP server using the 'User Query' with the recipient’s email address, and retrieve specific attributes defined under Mail Routing to determine the mail host for message delivery. mailHost - IP/FQDN of backend mail server to which the emails are routed. mailRoutingAddress - SMTP envelope (RCPT TO:) the email address to which the emails are delivered. On the AD server: Create new mailHost and mailRoutingAddress custom attributes on AD and assign the values to the attributes on the required user. Alternatively, use the existing unused attributes from the AD for Mail host attribute and Mail routing address attribute. In this example, the attributes 'division' and 'desktopProfile' are used, using the Attribute Editor: Configure the mailHost attribute for the required users, setting its value to the IP address or FQDN of the appropriate exchange or mail server. Optional: Configure the mailRoutingAddress attribute LDAP attribute for the required users, setting its value to the email address of the intended recipient on the email server. For the tests using the following configuration on the AD server: Mail Address division desktopProfile user1@labfmlemea.com test1@labfmlemea.com mailserver.labfmlemea.com internal1@labfml.com internal3@labfmlemea.com mailserver.labfmlemea.com The attributes for the account with mail address user1@labfmlemea.com have not been configured with any values for the attribute division and desktopProfile. The attributes for the account with mail address internal3@labfmlemea.com. The attributes for the account with mail address test1@labfmlemea.com. LDAP profile configuration on FortiMail: Create or edit an existing LDAP profile. The following is an example profile. Select the option to enable the Mail Routing Options. Note: LDAP cache is enabled by default. Go to Domain & User -> Domain -> Domain. Select a row to modify it. Expand the LDAP Option section. Configure the following: Mail routing profile. Assign the LDAP profile created for Mail Routing. mailHost and mailRoutingAddress configuration on the AD server: mailHost mailRoutingAddress Result on FortiMail if the LDAP profile is used for Mail Routing Set    Set Mail routed to mailHost and delivered to mailRoutingAddress. Set   Not set Mail routed to mailHost and delivered to original recipient address Not set Set Mail routed to SMTP server under Protected domain and delivered to mailRoutingAddress Not set Not set Mail routed to SMTP server under Protected domain and delivered to original recipient address The example logs for the emails received for the recipient user1@labfmlemea.com: The example logs for the emails received for the recipient test1@labfmlemea.com: The example logs for the emails received for the recipient Internal3@labfmlemea.com: