topic Re: ASA blocking email in Network Security

ASA blocking email

Namrepus1 — Mon, 11 Mar 2019 23:58:13 GMT

Please move to the appropriate area if I have posted in the wrong forum.

I am having an issue sending emails externally from an internal web host.

This is the log im seeing on the ASA. I am not able to ping the exchange from the server.

Can anyone tell me what entry I should be adding to allow the application stting on 192.168.99.11 to be able to send email to the exchange server located on 172.20.204.114?

Re: ASA blocking email

Karsten Iwen — Mon, 24 Sep 2012 17:00:27 GMT

Your Log doesn't show that the MailGuard is the problem here but disabling that function is very often the solution for all kind of issues with SMTP through the ASA:

policy-map global_policy

class inspection_default

no inspect esmtp

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ASA blocking email

Namrepus1 — Wed, 26 Sep 2012 14:54:46 GMT

Thank you Karsten.

I've tried your suggestion but looks as though no ESMTP maps are configured.

ASA blocking email

Karsten Iwen — Wed, 26 Sep 2012 15:03:54 GMT

It's not the ESMTP-Map. It's enough to have "inspect esmtp" enabled and the ASA will manipulate the SMTP-communication.

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ASA blocking email

Namrepus1 — Wed, 26 Sep 2012 15:15:54 GMT

Ok. These are my results. Looks as though inspection is not enabled.

ASA blocking email

Karsten Iwen — Wed, 26 Sep 2012 15:24:17 GMT

ok, then I would try to send a mail manually from the commandline ot the application-server:

http://www.linuxjournal.com/content/sending-email-netcat

What's the output of that?

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ASA blocking email

Namrepus1 — Wed, 26 Sep 2012 16:15:04 GMT

I cannot establish a telnet session with the SMTP server from the internal web host 192.xx.xx.xx

but I can from my machine 172.xx.xx.xx

Re: ASA blocking email

Karsten Iwen — Thu, 27 Sep 2012 05:33:00 GMT

Please attach your actual config to analyze that further.

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