Topic: Emails not being delivered from ISP

[justin]

I am trying to help a mate with his business network. I have setup a smoothwall firewall with port 25, 143 and 110 forwarded to the SME box.
I can telnet port 110 and 143 from external but not port 25. I can telnet the SME mail server port 25 from the lan but not external.

I have confirmed the firewall settings with a network engineer colegue. How can I setup a sniffer to see if the server is infact listening properly.

My setup is using a MX record hosted on IInet for domain.com.au to my static address but the emails are still at IInet as confirmed by IInet.
The mailboxes are locally created on the SME server. Does the SME server grab all the emails for domain.com.au from IINet using a pop account and the SME server dist the individual emails to the clients?. I am unsure how it works exactly. Can I check any logs on the SME server to see if the connection to IInet is failing or something like that. I looked at the Mail Log File analysis and there is an entry like this.

Mail Log File Analysis
Report generated: Sun 22 May 2005 05:29:13 PM EST
Reasons for deferral

One line per reason for deferral. Information on each line:
* del is the number of deliveries that ended for this reason.
* xdelay is the total xdelay on those deliveries.

 del     xdelay  reason
 773    2602.75  203.0.178.192 does not like recipient./Remote host said: 451 Static Address See http://www.dnsbl.sorbs.net/cgi-bin/lookup?NAME=Static Address/Giving up on 203.0.178.192./
 384  237720.79  Connected to 203.0.178.192 but connection died. (#4.4.2)/
  21    9709.72  Connected to 203.0.178.192 but connection died. Possible duplicate! (#4.4.2)/
  53    2158.03  Connected to 203.0.178.192 but sender was rejected./Remote host said: 451 DNS temporary failure (#4.3.0)/
 237    4737.89  Sorry, I couldn't find any host by that name. (#4.1.2)/
1175   10304.52  Sorry, I wasn't able to establish an SMTP connection. (#4.4.1)/

Could this be an IInet issue??



Please help.

[dhardy]

203.0.178.192 is an ISPs mailserver.

Have you configured SME to use 'Standard SMTP' for email retrieval? If so, you need to publish your public IP as the MX record.

DNS has funny rules, you need an A record that points to the IP and then an MX record that points to the A record.

The example from the logs shows your SME is trying to deliver mail to 203.0.178.192 - is this for email to your domain or email to another domain?

I suggest you check the Mail Retrieval settings in the Server Manager to verify that you have the ones you need and that you haven't put your ISPs details in the Delegate Mailservers 'Address of internal mail server' box.

Does the host name you have set up as the MX record resolve correctly from outside the network to your public IP?

Does your ISP permit incoming port 25 traffic on your public IP - do you need to specifically authorise or request it somehow?

HTH

David.

[justin]

David,

I may have mislead you in not saying that the setup was working perfectly a couple of days ago and then just stopped.
I spent the whole weekend trying to fix the problem and in the end told my mate to call a professional who knows SME Server/Linux.

I unfortunately have very little experience with this product but think it is very usable (Once I figure it out).
Sorry to trouble you but thanks for the feedback. It will be usefull for other jobs. I have just found out that this professional guy has got them going again.

Justin