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New Member

pix possible problem - not allowing smtp authentication

Pix 7.2.0 doesn't have "inspect esmtp" line added. But, authentication when sending a mail from wan doesn't work (mail server is in DMZ). When you try it from LAN - it works without problems.

Is it possible that pix block smtp authentication from WAN to DMZ, although there is no "inspect ESMTP" ?


Re: pix possible problem - not allowing smtp authentication


Without the 'inspect esmtp' line there is no (e)smtp protocol checking - there would be no reason the pix would drop the smtp for protocol reasons.

I would check your lan configuration to make sure that you don't have access-list issues - normally "inside' flows to the DMZ are allowed by default because of the security levels, but WAN to DMZ (assuming WAN had a lower security level than the DMZ) would not.


Please rate this message if it helped resolve some or all of your issue.

New Member

Re: pix possible problem - not allowing smtp authentication

Thanks for your answer.

I found out that ISP provider installed another firewall between WAN and our LAN. This is a kind of additional security for their key users. Guess what, their support told me "inspect esmtp is *on* by default".

Some security!!