Cisco Cisco Content Security Management Appliance M390 Guía Del Usuario
Chapter 10 Configuring SMTP Routing
10-4
Cisco IronPort AsyncOS 7.2.0 for Security Management User Guide
OL-21768-01
SMTP Routes Limits
You can define up to 10,000 routes. The final default route of
ALL
is counted as a
route against this limit. Therefore, you can define up to 9,999 custom routes and
one route that uses the special keyword
one route that uses the special keyword
ALL
.
SMTP Routes and DNS
Use the special keyword
USEDNS
to tell the appliance to do MX lookups to
determine next hops for specific domains. This is useful when you need to route
mail for subdomains to a specific host. For example, if mail to example.com is to
be sent to the company’s Exchange server, you might have something similar to
the following SMTP route:
mail for subdomains to a specific host. For example, if mail to example.com is to
be sent to the company’s Exchange server, you might have something similar to
the following SMTP route:
example.com exchange.example.com
However, for mail to various subdomains (foo.example.com), add an SMTP route
that looks like this:
that looks like this:
.example.com USEDNS
SMTP Routes and Alerts
Alerts sent from the appliance to addresses specified on the Security Management
appliance from Management Appliance > System Administration > Alerts
page (or the alertconfig command) follow SMTP Routes defined for those
destinations.
appliance from Management Appliance > System Administration > Alerts
page (or the alertconfig command) follow SMTP Routes defined for those
destinations.
SMTP Routes, Mail Delivery, and Message Splintering
Incoming: if one message has 10 recipients and they are all on the same Exchange
server, AsyncOS will open one TCP connection and present exactly one message
to the mail store, not 10 separate messages.
server, AsyncOS will open one TCP connection and present exactly one message
to the mail store, not 10 separate messages.
Outgoing: works similarly, but if one message is going to 10 recipients in 10
different domains, AsyncOS will open 10 connections to 10 MTAs and deliver
them one email each.
different domains, AsyncOS will open 10 connections to 10 MTAs and deliver
them one email each.