SMTP data timeout on connection

Eric M

Member
PartnerNOC
May 8, 2017
6
0
1
Philippines
cPanel Access Level
Root Administrator
Hi,

Has anyone experience smtp error such as email with specific attachment ( zip, jpg and pdf file are being not sent. However when the email being sent is plain text it is sent.

Also is it normal to have many "SMTP data timeout (message abandoned) on connection from" in our exim log?

Thank you!
 

cPanelMichael

Administrator
Staff member
Apr 11, 2011
47,911
2,234
363
Hello,

Has anyone experience smtp error such as email with specific attachment ( zip, jpg and pdf file are being not sent. However when the email being sent is plain text it is sent.
Check /var/log/exim_mainlog to see if you notice any error entries related to the message. EX:

Code:
exigrep MSGID /var/log/exim_mainlog
Repalce "MSGID" with the message ID of the affected message, as found when viewing the message header in an email client.

Also is it normal to have many "SMTP data timeout (message abandoned) on connection from" in our exim log?
This can sometimes relate to the following option under the "ACL Options" tab in "WHM >> Exim Configuration Manager >> Basic Editor":

Introduce a delay into the SMTP transaction for unknown hosts and messages detected as spam.

Per it's description:

The SMTP receiver will wait a few additional seconds for a connection when it detects spam messages in order to reduce inbound spam. The system excludes the following remote hosts from the delay: Neighbor IP addresses in the same netblock, Loopback addresses, Trusted Mail Hosts, Relay Hosts, Backup MX Hosts, Skip SMTP Checks Host, Sender Verify Bypass Hosts.
Thank you.
 

Eric M

Member
PartnerNOC
May 8, 2017
6
0
1
Philippines
cPanel Access Level
Root Administrator
Hi,

As per checking the exim log i am only seeing

2017-09-22 11:38:15 1dvEiH-0008VB-Hx SMTP data timeout (message abandoned) on connection from ([x.x.x.x]) [x.x.x.x]:59708 F=<[email protected]>
2017-09-22 11:41:07 1dvEl4-0001HF-4m SMTP data timeout (message abandoned) on connection from ([x.x.x.x]) [x.x.x.x]:59766 F=<[email protected]>
2017-09-22 11:44:08 1dvEnz-0002RO-Hj SMTP data timeout (message abandoned) on connection from ([x.x.x.x]) [x.x.x.x]:59856 F=<[email protected]>
2017-09-22 11:44:40 1dvEoV-0002dA-M2 SMTP data timeout (message abandoned) on connection from ([x.x.x.x]) [x.x.x.x]:59877 F=<[email protected]>
2017-09-22 11:45:33 1dvEpL-00034l-NO SMTP data timeout (message abandoned) on connection from ([x.x.x.x]) [x.x.x.x]:59900 F=<[email protected]>
2017-09-22 11:47:22 1dvEr6-0003nx-SJ SMTP data timeout (message abandoned) on connection from ([x.x.x.x]) [x.x.x.x]:59928 F=<[email protected]>
2017-09-22 11:48:14 1dvErw-00048f-QI SMTP data timeout (message abandoned) on connection from ([x.x.x.x]) [x.x.x.x]:59957 F=<[email protected]>
 

cPanelMichael

Administrator
Staff member
Apr 11, 2011
47,911
2,234
363
Hello,

Can you verify if the issue persists when temporarily disabling the following option under the "ACL Options" tab in "WHM >> Exim Configuration Manager >> Basic Editor"?

Introduce a delay into the SMTP transaction for unknown hosts and messages detected as spam.

Thank you.
 

cPanelMichael

Administrator
Staff member
Apr 11, 2011
47,911
2,234
363
Hello,

Can you open a support ticket using the link in my signature so we can take a closer look?

Thank you.
 

Eric M

Member
PartnerNOC
May 8, 2017
6
0
1
Philippines
cPanel Access Level
Root Administrator
Hi,

Thanks for the update. We have already applied the MTU but there are still experiencing the issue, The scenario is email with attachment are intermittent in being sent user can send attachment then after a few minutes they will not be able to send email with attachment again prompting the error smtp time out, however plain text emails are successfully being sent without errors.
 

cPanelMichael

Administrator
Staff member
Apr 11, 2011
47,911
2,234
363
Hello,

I see you have sent a response to the support ticket. I'll continue to monitor the ticket and update this thread with the outcome once it's closed.

Thank you.
 

cPanelMichael

Administrator
Staff member
Apr 11, 2011
47,911
2,234
363
Hello,

It was determined to be an issue with the network as opposed to the cPanel & WHM software. For instance, when pinging the remote IP address, package loss was noticed. You can test that by running the following command from your cPanel server:

Code:
ping $IP
Thank you.