Issue Plesk Can't forward Emails: Unknown User

[itdamherst]

Server operating system version

CentOS 7

Plesk version and microupdate number

18.0.52_build1800230516.12 os_CentOS 7

Trying to forward emails from a domain we no longer use (but host) to a new domain hosted by Google. The old domain is activated for email and forwarding addresses are setup. No bounces are received from test messages. In maillog I see messages such as this:

May 18 03:30:55 {domain} postfix-local[13326]: 6F12C83C3B: Unknown user: {xxx@domain}

SMTP is also running, and in fact it is often rejecting messages sent to non-existent users. It seems it is attempting to forward messages it is supposed to but failing.

 

[itdamherst]

log file continues:

May 18 03:30:55 {domain} postfix/pipe[13311]: 6F12C83C3B: to=<{xxx@domain}>, relay=plesk_virtual, delay=0.19, delays=0.01/0/0/0.17, dsn=2.0.0, status=sent (delivered via plesk_virtual service)
May 18 03:30:55 {domain} postfix/qmgr[4820]: 6F12C83C3B: removed

 

[Peter Debik]

I understand your question in this way: You have the same domain name configured hosted on Google and on your local Plesk server. When you create an email on your local Plesk server that should be forwarded to your domain hosted at Google?

In that case please disable the local email service or set it to "Disabled for Incoming Mails". The setting can be found in "Mail Settings" of the domain.

 

[itdamherst]

Not exactly. We used to use emails such as info@domain1.com, now we use emails such as info@domain2.com. I am trying to forward the domain1 emails to their corresponding domain2 addresses. The domain2 addresses are hosted at Google, whereas mail servers for domain1 are pointed to our Plesk server. I have already selected the option you mentioned above.

 

[Peter Debik]

Domain2, the one hosted externally, is disabled for incoming mail, yet delivery fails when mails are being forwarded? Have you set the correct MX entries for domain2? In case you are using the Bind (DNS) component on Plesk, do you have them set there, too, (just to make sure that your server is not querying itself instead of the real DNS server for that domain?

 

[itdamherst]

yes, that's right. Google takes care of the DNS entries for domain2 and when I do an MX lookup they all are pointed there. Bind is not installed on our server.

 

[itdamherst]

Pref	Hostname	IP Address	TTL
1	aspmx.l.google.com	172.253.62.27 Google LLC (AS15169)	60 min	Blacklist Check SMTP Test
1	aspmx.l.google.com	2607:f8b0:4004:c19::1b	60 min	Blacklist Check
5	alt1.aspmx.l.google.com	209.85.202.27 Google LLC (AS15169)	60 min	Blacklist Check SMTP Test
5	alt1.aspmx.l.google.com	2a00:1450:400b:c00::1a	60 min	Blacklist Check
5	alt2.aspmx.l.google.com	64.233.184.27 Google LLC (AS15169)	60 min	Blacklist Check SMTP Test
5	alt2.aspmx.l.google.com	2a00:1450:400c:c0b::1b	60 min	Blacklist Check
10	aspmx2.googlemail.com	209.85.202.27 Google LLC (AS15169)	60 min	Blacklist Check SMTP Test
10	aspmx2.googlemail.com	2a00:1450:400b:c00::1a	60 min	Blacklist Check
10	aspmx3.googlemail.com	64.233.184.26 Google LLC (AS15169)	60 min	Blacklist Check SMTP Test
10	aspmx3.googlemail.com	2a00:1450:400c:c0b::1b	60 min	Blacklist Check

 

[Peter Debik]

In that case I do not have an answer at this time. Maybe in this case it would be good to open a ticket with Plesk support so that an engineer can see and test this directly on your machine. It could be a product issue, because the outgoing mail option is fairly new. It could also be a misconfiguration, maybe also a filter that comes into play that we don't see in the excerpts above.

To sign-in to support please go to https://support.plesk.com

If you experience login issues, please see this KB article:
https://support.plesk.com/hc/en-us/...rt-plesk-com-and-password-reset-does-not-work

If you bought your license from a reseller, your reseller should provide support for you. If the reseller does not provide support, here is an alternative:
https://support.plesk.com/hc/en-us/articles/12388090147095-How-to-get-support-directly-from-Plesk-