Port forward Mail outbound ( only outgoing )

[chaiyut]

Hello

Information:
FW WAN ip - 1.1.1.7
FW VIP - 1.1.1.8
HAProxy ip - 192.168.1.10:10026
Docker host 1 ip - 192.168.1.11:10026
Docker host 2 ip - 192.168.1.12:10026

ISP --- FW --- HAProxy --- Docker host 1
                 |
                 |-------- Docker host 2

I build Docker and expose port 10026 to container port 25, then use HAProxy to load balance both mail docker ( only send out an email not for receive an email )

When send out an email the mail header said the mail come from 1.1.1.7 but I want to set an IP for 1.1.1.8 I already try with port forward but it's won't work. ( still IP 1.1.1.7 )

Try to check with Outbound NAT but not sure how to set and which IP should I use ?

[chaiyut]

Found the solution.

Go to outbound nat

Source:
Network 192.168.1.11/32
Destination:
Any - port 25

Translation:
Address:
1.1.1.8

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