How to send relayed email out of a certain interface

[bpeterson111]

Hello, I am looking for guidance on sending relayed email out of a certain logical interface tied to a specific IP.

I have mail policies in place both incoming an outgoing based on recipient domains and "any" sender.  But if mail is relayed from a web server through our appliance to Comcast or other domains, it gets sent using our default interface.

We are using a C380 with AsyncOS 9.6.0-042

Thanks,

[bpeterson111]

I guess another clarification I need is, what determines weather the message is incoming or outgoing? the question sounds silly but I have multiple domains that may be emailing each other.

[Mathew Huynh]

Hey bpeterson,

Inbound emails are generally matched under ACCEPT mail flow policies

Outbound emails are matched under RELAY mail flow policies.

Tracking/mail_logs will show outbound or inbound matching based on the mail flow policy used.

All deliveries are sent under the same interface defined in the CLI > deliveryconfig

You can specify which interface to use for all deliveries if you wish.

Else you will need to create static routes if you wish to use different source IP for different destinations.

If interface is set on Auto select, it will choose the source IP interface closes to the default gateway set.

Regards,

Matthew

[Boris Uskov]

Hello, team.

For this task you can also use Outgoing Content Filters and the action "Deliver from IP Interface".

[bpeterson111]

We currently have outgoing content filters to deliver from a certain IP.  Those content filters are then connected to outgoing mail policies with recipient domains defined.

Example 1: an alert is generated and sent using Ironport as the SMTP relay from member domain 1 to member domain 2.  With the current policies; that alert is sent to member domain 2's email server from member domain 2's IP interface.

Example 2: member domain 1 sends an alert the same way but it goes to Comcast.net.  Since no policy is defined for this it uses the default policy which sends it out the default interface.

Example 3: member domain 2 sends an alert the same way to Comcast.net  but how do I make sure it goes out the IP interface for member domain 2 instead of the default?  all of my outgoing policies are based on recipient IP's not senders.  And if I add senders then alerts from domain 1 to domain 2 wont use their correct IP interfaces

[Boris Uskov · Accepted solution]

Hello,

I have drawn a schema to understand the question (see the attach). Please, confirm, if the schema is correct.

According to the schema:

Example 1. Email from domain1 is delivered to domain2 with IP address 192.168.2.168. It is Ok (expected behaviour)

Example 2. Email from domain1 is delivered to comcast.net with IP address 10.1.1.1. It is also Ok (expected behaviour), because of default gateway.

Example 2.  Email from domain2 is delivered to comcast.net with IP address 10.1.1.1. But you want to deliver Email from domain2 with IP address 192.168.2.1. 

Is it correct? If yes, you can simply create an additional Outgoing Conternt Filter. Please, see the screenshot "Filter.jpg".

Please, pay the attention, the order of new Outgoing Content filter does matter. You should be sure, that the new Outgoing Content filter will not be overrided by previous Content Filters.

You can attach the new Content Filter to Outgoing Mail Policies, even if Outgoing Mail Policies does not rely on Sender's information (IP addresses, mail addresses or any other information).

[bpeterson111]

Thanks,  your schema looks correct.  I was hoping there was an easier way.  It sounds like I may need to create more outgoing filters for each member if I want them to be able to relay mail properly.