SMTP Transaction Time

Community Support
1

Hello,

Following a test on Mxtoolbox of my SMTP server, it appears that the SMTP transaction time is really long.

Here are the details :
SMTP Transaction Time :
6.173 seconds - Warning on Transaction Time

Is the problem that it’s a test that is detected as spam or is it the server ?

Thanking you for your help,

Charles

2

Hi @Charles

Show the Session Transcript.

3

Hello @sahsanu,

Below is the session:

Screenshot_20250415-000659
Screenshot_20250415-000659719×971 38.7 KB

4

And the test result:

Screenshot_20250415-001015
Screenshot_20250415-001015711×759 51.8 KB

5

Looks like a slow dns resolution on your server’s side.

6

Show the output of these commands:

dig -x 142.251.173.109 +noall +stat +ans
dig -x 74.125.206.26 +noall +stat +ans
dig -x 1.2.3.4 +noall +stat +ans
dig mx gmail.com +noall +stat +ans
dig mx mxtoolbox.com +noall +stat +ans
7

I have this result for my name servers:

Screenshot_20250415-001824
Screenshot_20250415-001824720×764 62.7 KB

8

I’m not asking for that data but as you posted it, you should fix your dns resolution, dns2.lws-hosting.com is not able to resolve your domain.

9

Sorry @sahsanu, I don’t know how to use these commands you sent me yet

10

You will need to log in to your server via SSH to execute the commands. If you’re unfamiliar with this process, it may be difficult for us to assist you effectively

1 Like
11

Thank you for the information, I’ll ask my hosting provider’s outsourcing to look into this for me.

2 Likes
12

You can also try reducing the value of the ‘rfc1413_query_timeout =’ option in the ‘/etc/exim4/exim4.conf.template’ file from the terminal or via https://sub.domain.tld:8083/edit/server/exim4/.

Be careful because Fail2Ban may ban the MxToolBox IP after several tests and you will have to remove it manually from the list.

13

Hello @Wibol,

The value is already at 0 s