Show source IP behind NAT
Dear Friends,
I'm a newbie user of ZyXel USG-200.
I need to reach SMTPs service behind the firewal. Following some guide i setup correctly the NAT service.
Now the SMTPs is are available.

I check the log on SMTPs server and all incoming connections comes from the IP of the firewall
postfix/smtpd[8745]: DDEF012004D: client=unknown[192.168.1.200]
postfix/cleanup[8746]: DDEF012004D: message-id=<CANRN+XAFW50ABRnW7Gcs7fB=0f1gOK7H_smb8a3VTTBqmGQQOQ@mail.gmail.com>
postfix/qmgr[381]: DDEF012004D: from=<*************@gmail.com>, size=3762, nrcpt=1 (queue active)
In this example the IP of google is replaced by the IP of the LAN of firewall (192.162.1.200).
I try to find how to resolve this issue by myself but without success.
WAN2_IP : The public IP of firewall
LAN IP : 192.168.1.200 of firewall
MailCow: IP of mailserver
Can someone help me?
Many thanks
AndreA
I'm a newbie user of ZyXel USG-200.
I need to reach SMTPs service behind the firewal. Following some guide i setup correctly the NAT service.
Now the SMTPs is are available.

I check the log on SMTPs server and all incoming connections comes from the IP of the firewall
postfix/smtpd[8745]: DDEF012004D: client=unknown[192.168.1.200]
postfix/cleanup[8746]: DDEF012004D: message-id=<CANRN+XAFW50ABRnW7Gcs7fB=0f1gOK7H_smb8a3VTTBqmGQQOQ@mail.gmail.com>
postfix/qmgr[381]: DDEF012004D: from=<*************@gmail.com>, size=3762, nrcpt=1 (queue active)
In this example the IP of google is replaced by the IP of the LAN of firewall (192.162.1.200).
I try to find how to resolve this issue by myself but without success.
WAN2_IP : The public IP of firewall
LAN IP : 192.168.1.200 of firewall
MailCow: IP of mailserver
Can someone help me?
Many thanks
AndreA
0
All Replies
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You must of setup a routing rule for this to happen as is you don't have a routing rule from WAN to LAN SNAT then this would not happen so remove it.0
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Hi @maruscya
It seems there is a policy route’s next hop be set to lan such as following example.
Can you check that and disable this policy to verify it again?You can refer to this link:Thanks.0
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