IronPort - advanced configuration guide

Chapter 2 Configuring Routing and Delivery Features
Controlling TLS
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These values are explained in Table 2-8.
Table 2-8 Values in the Destination Controls Table
Field Description
Concurrent
Connections
Maximum
Messages Per
Connection
The maximum number of outbound connections that will be made by the Cisco
IronPort appliance to a given host. (Note that the domain can include your internal
groupware hosts.)
The maximum number of messages allowed for a single outbound connection from the
Cisco IronPort appliance to a given host before initiating a new connection.
Recipients The maximum number of recipients allowed within the given period of time. “None”
denotes that there is no recipient limit for the given domain.
The minimum period of time — between 1 and 60 minutes — that the Cisco IronPort
appliance will count the number of recipients. Specifying a time period of “0” disables
the feature.
Note If you change the recipient limit, AsyncOS resets the counters for all messages
already in the queue. The appliance delivers the messages based on the new
recipient limit.
Apply Limits Specifies whether the limit will be applied (enforces) to the entire domain or to each
mail exchange IP address specified for that domain. (Many domains have multiple MX
records.)
This setting applies to connection, message, and recipient limits.
Specifies whether the limit will be applied system-wide or for each Virtual Gateway
address.
Note If you have configured groups of IP addresses, but you have not configured
virtual gateways, do not configure apply limits per each virtual gateway. This
setting is intended only for systems configured to use virtual gateways. For
information on configuring virtual gateways, see Using Virtual Gateway
Technology, page 2-59.
Note If limits are applied per each Virtual Gateway address, you can still effectively implement system-wide
limits by setting the Virtual Gateway limit to the system-wide limit you want divided by the number of
possible virtual gateways. For example, if you have four Virtual Gateway addresses configured, and you
do not want to open more than 100 simultaneous connections to the domain yahoo.com, set the Virtual
Gateway limit to 25 simultaneous connections.
Note The delivernow command, when acting on all domains, resets all counters tracked in the destconfig
command.
You can also configure the TLS (Transport Layer Security) on a per-domain basis. If the “Required”
setting is specified, a TLS connection will be negotiated from the Cisco IronPort appliance listener to
MTA(s) for the domain. If the negotiation fails, no email will be sent through the connection. For more
information, see Enabling TLS and Certificate Verification on Delivery, page 1-29.
Cisco IronPort AsyncOS 7.6 for Email Advanced Configuration Guide
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