Firewall/NAT

I have an email server running behind monowall. I am starting to get blocked emails due to the fact that the recipiants mail server thinks the email is coming from x.x.x.34 (monowall address) the mail server resides at x.x.x.37 . Is there a configuration change I can make on the monowall?

I would assume that if you are doing 1:1 static NAT'ing, the traffic from your Exchange server would be sourced from it's publically assigned IP.  (and, obviously, if your Exchange server is in a DMZ and you are not doing NAT'ing, it should be fine as well)

However, perhaps you need to create a specific outbound NAT rule in addition to the 1:1 NAT.  (I would hope not as that defeats half the purpose of having 1:1 NAT'ing functionality in the first place)

CMB should be able to provide you with more guidance.

If you're using 1:1 NAT it automatically goes out on the right IP. If it's going out on a different IP, you must be using Server NAT, in which case you either need to change it to 1:1, or use Advanced Outbound NAT to direct outbound traffic to the appropriate IP.

I have an email server running behind monowall. I am starting to get blocked emails due to the fact that the recipiants mail server thinks the email is coming from x.x.x.34 (monowall address) the mail server resides at x.x.x.37 . Is there a configuration change I can make on the monowall?

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