Question Send mail using a site Not hosted on Plesk.

[hasaanch]

Server operating system version

Ubuntu 22.04.4 LTS

Plesk version and microupdate number

Version 18.0.61 Update #5

Hi there,
I want to use my Plesk server as a mail server.
I am using WordPress websites, which require sending emails. Before, I used MailJet (a service similar to SendGrid) as my SMTP service.
I can send emails fine from the sites that are hosted on My Plesk server.

These are the steps I am following for sending emails from Non-Hosted Sites.

1. Add Domain in Plesk. (Not changing the A record to Plesk)
2. In Mail Options enabling both outgoing and incoming.
3. Create a mail address in Mail Accounts.
4. Using my primary domain as an SMTP host (mail.domain.com) that resolves to the server, SPF records are configured. TLSA records are configured. (I am using the same SMTP host for hosted sites and mails are working fine there).
5. Use the Mail Account username and password for authentication.

When I try to send mail, it gives a timeout and never connects to the server.
I tried adding the IP of the non-hosted site to the Whitelist but got the same result.

 

[hasaanch]

Here's the mail server test.

SPF Test

 

[Kaspar@Plesk]

4. Using my primary domain as an SMTP host (mail.domain.com) that resolves to the server, SPF records are configured. TLSA records are configured. (I am using the

Instead of using the primary domain a SMTP host, try using the hostname of your Plesk server as SMTP host.

 

[hasaanch]

Tried both the Hostname and IP address.
Same issue.

 

[Kaspar@Plesk]

Did you (double) check that the ports (465 and/or 587) are open on both servers? Did you test whether or not you can manually make a connection to the Plesk server with an email client (Outlook, Thunderbird or the mail app on your phone) with the same user credentials?

 

[hasaanch]

Did you (double) check that the ports (465 and/or 587) are open on both servers? Did you test whether or not you can manually make a connection to the Plesk server with an email client (Outlook, Thunderbird or the mail app on your phone) with the same user credentials?

Yes, I am sending mails from my other domains that are hosted on plesk using port 587.
For the non-hosted site I tried sending mails using MailJet on port 587 and it worked fine but same timeout when tried my own server.

 

[Kaspar@Plesk]

Maybe the IP address of the Wordpress server got banned by fail2ban on the Plesk server?

 

[hasaanch]

Hi @Kaspar@Plesk ,
My Plesk firewall and Fail2Ban are both disabled. So, it shouldn't be the issue.

 

[Kaspar@Plesk]

I am running out of suggestions. To me, the timeout error indicates that the Wordpress server can't even connect to the Plesk server. Seems like something is blocking the connection. My guess would be something on the Wordpress server. (But it could be something else too). Do you have SSH access to it? If you do, you can try to make secure SMTP connection to your Plesk server on port 587. For example with openssl s_client -starttls smtp -connect <plesk server host name>:587 (replace <plesk server host name> with the hostname of your Plesk server).