Solved

Cisco ASA 5510 and portforwarding for SMTP

Posted on 2010-09-09
10
819 Views
Last Modified: 2012-05-10
Good Morning,
I recently experienced an issue where my Cisco ASA 5510 just magically stopped forwarding SMTP traffic from outside my organization.  I have never used a ASA before.  My OWA access works and internal mail still flows.  IT is when someone outside the organization attempts to email someone here at my company, the email either does not make it and they get an errror message or it is very extremely slow in getting here.

I have attached a copy of the running config from my ASA.
running-config
0
Comment
Question by:dillingerm
  • 3
  • 2
  • 2
  • +2
10 Comments
 
LVL 4

Expert Comment

by:mpickreign
ID: 33637186
The ASA config looks good, and the fact that you say some mail comes in, albeit slowly, indicates the issue is elsewhere. If the ASA was blocking mail, it would never come through.

What kind of error messages are the remote senders getting?  
0
 

Author Comment

by:dillingerm
ID: 33637229
This is what I get when I try to send my self an email from my hotmail:
This is an automatically generated Delivery Status Notification.
 
Delivery to the following recipients failed.
 
  <email address>

I also am not able to telnet to my email server from outside either.  I had posted up in the exchange blogs and they advised me to come look here.  I think it would almost have to do with the firewall seeing how I  am not able to telnet into port 25 from outside.  My outisde ip for email is 64.187.68.37-this is where i am unable to telnet to
0
 
LVL 4

Expert Comment

by:mpickreign
ID: 33637401
Actually it looks like your external IP for mail is 64.187.68.34  and I am able to telnet into it on 25.
0
PRTG Network Monitor: Intuitive Network Monitoring

Network Monitoring is essential to ensure that computer systems and network devices are running. Use PRTG to monitor LANs, servers, websites, applications and devices, bandwidth, virtual environments, remote systems, IoT, and many more. PRTG is easy to set up & use.

 

Author Comment

by:dillingerm
ID: 33639782
That is my old mail server.  My previous colleague replaced it with a new box before his departure.  I removed that mx record and then things started going funky after that
0
 
LVL 3

Expert Comment

by:Mystique_87
ID: 33640180
--which is the mail server you are currently using?
Is it 10.10.4.7 or 10.10.4.12
--tell us the inside and the outside ip address of the mail server you are currently using
0
 

Author Comment

by:dillingerm
ID: 33640208
10.10.4.12 is Inside IP of Email Server
64.187.68.37 is outside IP of Email server.
0
 
LVL 13

Accepted Solution

by:
3nerds earned 500 total points
ID: 33640548
You access list is wrong, this line:

access-list OUT->IN extended permit tcp any eq smtp host SHSMXC001_Inside eq smtp

should be

access-list OUT->IN extended permit tcp any eq smtp host SHSMXC001 eq smtp

As a side note because your using a PAT for you outside to inside when you send mail out it will still go out 64.187.68.34 which is a good thing because you do not have a reverse record set for .37 and this would cause your mail to end up in smap folders.

Regards,

3nerds
0
 
LVL 3

Expert Comment

by:Mystique_87
ID: 33640804
So the mail server 10.10.4.12 gets natted to 64.187.68.37.
So anybody who wants to access the mail server from outside has to access using the public ip 64.187.68.37.

so add another entry to thr access-list OUT->IN:
access-list OUT->IN extended permit tcp any host SHSMXC001 eq smtp

also add another static entry:

static(inside,outside) SHSMXC001 eq 25 SHSMXC001_Inside eq 25
0
 
LVL 69

Expert Comment

by:Qlemo
ID: 34391603
This question has been classified as abandoned and is being closed as part of the Cleanup Program.  See my comment at the end of the question for more details.
0

Featured Post

VMware Disaster Recovery and Data Protection

In this expert guide, you’ll learn about the components of a Modern Data Center. You will use cases for the value-added capabilities of Veeam®, including combining backup and replication for VMware disaster recovery and using replication for data center migration.

Question has a verified solution.

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

Quality of Service (QoS) options are nearly endless when it comes to networks today. This article is merely one example of how it can be handled in a hub-n-spoke design using a 3-tier configuration.
If you use NetMotion Mobility on your PC and plan to upgrade to Windows 10, it may not work unless you take these steps.
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…
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…

806 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