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New Member

Pix 520 translation problems between inside and DMZ mail server

I have a Pix 520 running v6.2(1) Inside network is 172.16.x..x with about 500 users accessing a mail server on the dmz at Everything works fine, but after a while, I will start to get reports that random hosts on the inside network can no longer communicate with the mail server on the DMZ. You can't even telnet to the mail ports. Other PC's are working just fine. If I do a clear xlate command on the Pix, the "blocked" hosts can immediately communicate with the mail server again. After about 12 hours or so, the problem will re-appear on another set of machines.

This problem never occurs when doing a translation through the outside interface for internet access. Only when communicating with the DMZ.

Anyone got a suggestion as to where/what to look for?

Relevant configs from my Pix.

global (outside) 10 interface

global (dmz) 10

nat (inside) 10 0 0

New Member

Re: Pix 520 translation problems between inside and DMZ mail ser

You should use the next command, in global configuration

established tcp 25 0