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PIX515 with PIXOS 6.3(4) NAT Problem

Dear All,

I am running a PIX 515 with OS 6.3(4).

The PIX has three interfaces outside, inside and dmz.

There is an exchange mail server in the dmz area. Its IP add is And it is natted to an outside address like for example. At the beginning, everything is working fine. But after some time, the mail server will not be able to access the internet. I use my computer to connect to the internet directly using the, the link is fine and I can access the internet. After changing the outside nat address to, the mail server is working again.

Can anyone give me a clue? I'm really frustrated about this problem.

Community Member

Re: PIX515 with PIXOS 6.3(4) NAT Problem

By not working, are you meaning that outgoing email stops or you are seeing emails being rejected by other mail servers (like AOL)?

Can you browse the internet from your mail server when the problem is occuring or is it just email?

Community Member

Re: PIX515 with PIXOS 6.3(4) NAT Problem

I mean every service is not working. And I can not browse the internet from the mail server.

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