Filter
Top Products
Restricted SMTP Relay and SMTP Authentication Interaction
The following table describes the results of using restricted SMTP relay and SMTP
authentication (see “SMTP Authentication” on page 64) in various combinations.
SMTP requires authentication Restricted SMTP relay Result
On O All mail servers must
authenticate before Mail
service accepts mail for relay.
Your local mail users must also
authenticate to send mail out.
On On Approved mail servers can
relay without authentication.
Servers you haven’t approved
can relay after authenticating
with Mail service.
O On Mail service can’t be used for
open relay. Approved mail
servers can relay (without
authenticating).
Servers that you haven’t
approved can’t relay unless
they authenticate, but they can
deliver to your local mail users.
Your local mail users don’t need
to authenticate to send mail.
This is the most common
conguration.
Rejecting SMTP Connections from Specic Servers
Mail service can reject unauthorized SMTP connections from hosts on a disapproved-
hosts list that you create. Mail trac from hosts on this list is denied and the SMTP
connections are closed after posting a 554 SMTP connection refused error.
To reject unauthorized SMTP connections from specic servers:
1 In Server Admin, select a computer in the Servers list, then select Mail.
2 Click Settings.
3 Select the Relay tab.
4 Click the “Refuse all messages from these hosts and networks” checkbox.
5 Edit the list of servers by choosing one of the following:
Click the Add (+) button to add a host to the list. Â
Click the Remove (-) button to delete the selected host from the list. Â
Click the Edit (/) button to change the selected host from the list. Â
32 Chapter 2 Mail Service Setup