Solved

Cisco ASA drops email (SMTP) from some domains

Posted on 2010-11-11
2
1,310 Views
Last Modified: 2012-05-10
We are missing some emails from Domains.  I have enclosed the logs for one paticular domain that can not send back to us.


Built inbound TCP connection 14677106 for outside: xxx.xxx.250.xx/59339 (xxx.xxx.250.99/59339) to inside:xxx.x.x.xx/25 (XX.151.25.XX/25)


Deny TCP (no connection) from xxx.xxx.250.99/59339 to XX.151.25.XX/25 flags ACK  on interface outside
Deny TCP (no connection) from xxx.xxx.250.99/59339 to XX.151.25.XX/25 flags ACK  on interface outside
Deny TCP (no connection) from xxx.xxx.250.99/59339 to XX.151.25.XX/25 flags PSH ACK  on interface outside
Deny TCP (no connection) from xxx.xxx.250.99/59339 to XX.151.25.XX/25 flags ACK  on interface outside
Deny TCP (no connection) from xxx.xxx.250.99/59339 to XX.151.25.XX/25  flags ACK  on interface outside
Deny TCP (no connection) from xxx.xxx.250.99/59339 to XX.151.25.XX/25 flags ACK  on interface outside

Not sure why some are coming through and others are not.
0
Comment
Question by:Tech_guy
2 Comments
 
LVL 20

Accepted Solution

by:
EndureKona earned 250 total points
ID: 34114655
0
 
LVL 76

Assisted Solution

by:Alan Hardisty
Alan Hardisty earned 250 total points
ID: 34116702
The CISCO ASA will have ESMTP Inspect / Inspect ESMTP (equivalent of SMTP Fixup) - this is well known to cause mail-flow issues and should be disabled on your ASA device.

If you can't find SMTP Fixup - look for ESMTP Inspect and disable it.
0

Featured Post

Networking for the Cloud Era

Join Microsoft and Riverbed for a discussion and demonstration of enhancements to SteelConnect:
-One-click orchestration and cloud connectivity in Azure environments
-Tight integration of SD-WAN and WAN optimization capabilities
-Scalability and resiliency equal to a data center

Question has a verified solution.

If you are experiencing a similar issue, please ask a related question

Concerto Cloud Services, a provider of fully managed private, public and hybrid cloud solutions, announced today it was named to the 20 Coolest Cloud Infrastructure Vendors Of The 2017 Cloud  (http://www.concertocloud.com/about/in-the-news/2017/02/0…
A list of top three free exchange EDB viewers that helps the user to extract a mailbox from an unmounted .edb file and get a clear preview of all emails & other items with just a single click on mailboxes.
In this video we show how to create an email address policy in Exchange 2013. We show this process by using the Exchange Admin Center. Log into Exchange Admin Center.:  First we need to log into the Exchange Admin Center. Navigate to the Mail Flow…
After creating this article (http://www.experts-exchange.com/articles/23699/Setup-Mikrotik-routers-with-OSPF.html), I decided to make a video (no audio) to show you how to configure the routers and run some trace routes and pings between the 7 sites…

792 members asked questions and received personalized solutions in the past 7 days.

Join the community of 500,000 technology professionals and ask your questions.

Join & Ask a Question