How can I configure round robin style outbound connections in Cisco Email Security Appliance?

Introduction

This document describes how to balance in round robin style outbound connection on Cisco Email Security Appliance (ESA).

How can I configure round robin style outbound connections in Cisco Email Security Appliance (ESA)?

In AsyncOS you can configure round robin delivery using the smtproutes command. Each new connection
made will hop between the configured servers. Note that this will only balance new connections
made to the target server and not the number of emails sent down each pipe.

mail.example.com> smtproutes
There are no routes configured.
Choose the operation you want to perform:
- NEW - Create a new route.
- IMPORT - Import new routes from a file.
[]> new
Enter the hostname for which you want to set up a permanent route.
Partial hostnames such as ".example.com" are allowed.
Use "ALL" for the default route.
[]> ironport.com
Enter the destination hosts, separated by commas, which you want mail for
 ironport.com to be delivered.
Enter /dev/null by itself if you wish to discard the mail.
[]>192.168.0.1,192.168.0.2,192.168.0.3
Mapping for ironport.com to 192.168.0.1, 192.168.0.2, 192.168.0.3 created.
There are currently 1 routes configured.
Choose the operation you want to perform:
- NEW - Create a new route.
- DELETE - Remove a route.
- PRINT - Display all routes.
- IMPORT - Import new routes from a file.
- EXPORT - Export all routes to a file.
- CLEAR - Remove all routes.
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