Messages from user disconnect

Problem reported by Brian Raboin - 4/28/2021 at 6:17 AM

Resolved

Smatermail server SmarterMail Enterprise 100.0.7719.31036 ( SmarterMail Diagnostics all pass)

Smartermail server has users that cannot receive mail from the dotloop mail servers. Their messages disconnect in the manner below. Some messages do get through but most do not. All other incoming mail seems to be fine. We are just aware of this one domain. I cannot reach the sender server admins to discuss.

I am trying to confirm that there is nothing on the Smartermail server causing these to fail.

I have whitelisted the sending domain on the domain level.

I am not sure why it is adding "bounces" to the front of address either but on the message that delievered from dotloop, the message arrive with "bounces" appended.

Secondly, I'm not sure if there is a way to track if there are other incoming messages that are failing in the same way.

Smartermail server:mail.countryfarm.com (not real hostname, real hostname is set up properly, RDNS is OK)

from smtp log, one message all others are similar. the one that I found that got through simply didn't disconnect.

[2021.04.26] 15:53:05.456 [192.254.122.57][44489167] rsp: 220 mail.countryfarm.com
[2021.04.26] 15:53:05.456 [192.254.122.57][44489167] connected at 4/26/2021 3:53:05 PM
[2021.04.26] 15:53:05.456 [192.254.122.57][44489167] Country code: US
[2021.04.26] 15:53:05.503 [192.254.122.57][44489167] cmd: EHLO o1.email.dotloop.com
[2021.04.26] 15:53:05.503 [192.254.122.57][44489167] rsp: 250-mail.countryfarm.com Hello [192.254.122.57]250-SIZE 31457280250-AUTH LOGIN CRAM-MD5250-8BITMIME250-DSN250 OK
[2021.04.26] 15:53:05.549 [192.254.122.57][44489167] cmd: MAIL FROM:<bounces+814510-32c2-bob=countryfarm.com@email.dotloop.com>
[2021.04.26] 15:53:05.549 [192.254.122.57][44489167] senderEmail(1): bounces+814510-32c2-bob=countryfarm.com@email.dotloop.com parsed using: <bounces+814510-32c2-bob =countryfarm.com @email.dotloop.com>
[2021.04.26] 15:54:05.551 [192.254.122.57][44489167] disconnected at 4/26/2021 3:54:05 PM
[2021.04.26] 15:56:07.638 [192.254.122.57][44489167] rsp: 250 OK <bounces+814510-32c2-bob=countryfarm.com@email.dotloop.com> Sender ok
[2021.04.26] 15:56:07.638 [192.254.122.57][44489167] Sender accepted. Weight: -2. Block threshold: 30.

Thanks

5 Replies

Reply to Thread

Kyle Kerst Replied

4/28/2021 at 7:48 AM

Employee Post Marked As Resolution

Hello! I reviewed your log traffic and see a significant delay between the MAIL FROM and the disconnect event, which is usually caused by delays in spam checks or DNS lookups. To resolve this I recommend you first navigate to Settings>General and set the following DNS servers temporarily to see if the behavior improves:

1.1.1.1 (Cloudflare DNS)

8.8.8.8 (Google DNS)

Once those are in place, head over to Settings>Antispam>RBLs/URIBLs and sort that list by Average Time. Any lists here showing a response time of 1000Ms+ should be investigated or disabled to ensure smooth delivery. I hope this helps!

Kyle Kerst System/Network Administrator SmarterTools Inc. (877) 357-6278 www.smartertools.com