Symantec Mail Security, Administration Manual

Page: 25 / 258

25 Configuring system settings
Configuring host (Scanner) settings
Advanced SMTP settings
Use the MTA Configuration portion of the page to specify the MTA host name.
The MTA Host Name gives you the ability to define the Hello banner during the
initial portion of the SMTP conversation.
Use the following advanced inbound SMTP settings to further define your SMTP
configuration:
Use the following advanced outbound SMTP settings to define further your
SMTP configuration:
Table 2-1 Inbound SMTP advanced setting descriptions
Item Description
Maximum number of
connections Sets the maximum number of simultaneous inbound
connections allowed. Additional attempted connections are
rejected. The default is 2,000 connections.
Maximum number of
connections from a single
IP address Sets the maximum number of simultaneous inbound
connections allowed from a single IP address. Additional
connections for the same IP address will be rejected. The
default is 20. You can also limit the number of connections
from a single IP address per time period. Click Policies >
Attacks in the Control Center.
Maximum message size in
bytes Sets the maximum size of a message before it is rejected. The
default is 10,485,760 bytes.
Maximum number of
recipients per message Sets the maximum number of recipients for a message. The
default is 1,024 recipients.
Insert RECEIVED header
to inbound messages Places a RECEIVED header in the message during inbound
SMTP processing.
Enable reverse DNS
lookup Causes the system to perform reverse DNS lookup on the
SMTP client IP addresses to resolve the IP address to a name
when checked. This is the default condition. When
unchecked, reverse DNS lookup is not performed for inbound
messages.
Table 2-2 Outbound SMTP advanced setting descriptions
Item Description
Maximum number
of connections Sets the maximum number of permissible simultaneous outbound
connections. Additional attempted connections are rejected. The
default is 2,000 connections.