Postfix configuration: error regarding host name and virtual domains

[B_P]

Dear all,

I run a virtual server (Ubuntu 12.04, Plesk 12, Postfix 2.9.6) using plesk to manage multiple domains.
The server address is server.domain1.com. I use plesk to also manage domain1.com regarding all services, including DNS and mail.

What I just found is that postfix sometimes issues the following warning:
server postfix/trivial-rewrite[7397]: warning: do not list domain server.domain1.com in BOTH mydestination and virtual_alias_domains


The essential part of my main.cf is:
myhostname = server.domain1.com
mydestination = localhost.$mydomain, localhost.localdomain, localhost
virtual_mailbox_domains = $virtual_mailbox_maps, hash:/var/spool/postfix/plesk/virtual_domains
virtual_alias_maps = $virtual_maps, hash:/var/spool/postfix/plesk/virtual
virtual_mailbox_maps = , hash:/var/spool/postfix/plesk/vmailbox
virtual_transport = plesk_virtual

And /var/spool/postfix/plesk/virtual_domains contains amongst others:
domain1.com domain1.com/

I do not have any issues with receiving or sending e-mails right now, but would like to get rid of the error message however.

Could it be the problem that postfix automatically sets mydomain to $myhostname with skipping the first part (i.e., mydomain is implicitly set to domain1.com)?
Should I manually set mydomain to server.domain1.com instead? Any other recommendations? Since mydomain seems to be used in multiple options (http://www.postfix.org/postconf.5.html#mydomain), I wonder what I might destroy with changing this? As all mail services run without any further troubles at the moment, I don't want to break this...

As I assume that quite some people use a plesk-based server to manage the domain to which the server itself belongs to, I would assume that there should be a general fix/check to updated mydomain accordingly?

 

[UFHH01]

Hi B_P,

Should I manually set mydomain to server.domain1.com instead?

No, please use:

mydestination = localhost.domain1.com, localhost, localhost.localdomain

... to avoid warning - messages as desccribed.

Such a warning may occur, if you changed the hostname over the Plesk Control Panel to the same name of a used domain with Plesk. Please be aware, that such a message is only a "warning" - and nothing more. It shouldn't cause any issues at all.

 

[B_P]

Hi UFHH01,

No, please use:

mydestination = localhost.domain1.com, localhost, localhost.localdomain

... to avoid warning - messages as desccribed.

Since mydomain is equal to domain1.com, what does this change?
What would happen if I changed mydomain to the full host name? I went through the whole Postfix config description and did not find a setting where I would assume any conflict.

Such a warning may occur, if you changed the hostname over the Plesk Control Panel to the same name of a used domain with Plesk. Please be aware, that such a message is only a "warning" - and nothing more. It shouldn't cause any issues at all.

That is exactly the case as I mentioned before. But if it does not cause any issues, the warning should not appear?

 

[UFHH01]

Hi B_P,

Since mydomain is equal to domain1.com, what does this change?

well, you can answer the question by yourself, B_P, because you can see that "server.domain1.com" isn't the same as "localhost.domain1.com". As you already read in the documentation,

"$mydomain" seems to be used in multiple options"
​

and therefore may conflict with standard ( and not explicit, manually changed in your main.cf ) settings from postfix - you therefore experienced this warning in your logs from time to time.


Postfix knows 4 address classes: "local domains", "relay domains", "virtual_alias domains" and "virtual_mailbox domains". If a domain exists in more than one of these 4 classes, you will receive such a warning, because it could be ( a very rare existent case!!! ), that a never-ending loop could be created, if postfix isn't able to sort an eMail to one of it's 4 classes. The different specific "local" definitions for "mydestination" should prevent such a never-ending loop creation.