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Topic: disable sender reject for allowed hosts

We now have a second Mailserver for sending out special mails to customers from the datacenter. This host uses a different FQDN and IP-Address but sends also under the same domain.

so basically the domain is the same for both (example.org) just the hostname is different mail and mail2.

now i just want to send some mails to mail. (some admin mails)
but i surely get

Recipient address rejected: User unknown in virtual mailbox table; in the mail.log because root@example.org is not known in the table.

can i disable that feature for this specific mail2 host? if not, how can i disable this completly?

Thanks for any help!

==== Provide required information to help troubleshoot and get quick answer ====
- iRedMail version: 0.7.4
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2

Re: disable sender reject for allowed hosts

No one can help me with this??

3

Re: disable sender reject for allowed hosts

martinseener wrote:

Recipient address rejected: User unknown in virtual mailbox table; in the mail.log because root@example.org is not known in the table.

can i disable that feature for this specific mail2 host? if not, how can i disable this completly?

Sorry, I don't quite understand what you want to disable. sad

It complains you don't have root@example.org on the server, you can either add this account, or append IP address of mail2 in Postfix setting "mynetworks =" on mail.

4 (edited by martinseener 2012-05-14 18:05:30)

Re: disable sender reject for allowed hosts

Hi,

i tried adding the IP of mail3.example.org to the main mailservers main.cf file in "mynetworks" where now only 127.0.0.0/8 is attended in 3 different ways.
as FQDN, as x.x.x.x/Y (network-ip+netmask) and single IP of the mailserver - everytime postfix restart but it doesnt help the following error appears in the "receipient" mailserver (not the sending mailserver) (x.x.x.x is here the sending mail3 mailservers IP)

May 14 12:03:01 mail1 postfix/smtpd[28105]: connect from unknown[x.x.x.x]
May 14 12:03:01 mail1 postfix/smtpd[28105]: NOQUEUE: reject: RCPT from unknown[x.x.x.x]: 550 5.1.1 <mseener@example.org>: Recipient address rejected: User unknown in virtual mailbox table; from=<> to=<mseener@example.org> proto=ESMTP helo=<mail3.example.org>
May 14 12:03:01 mail1 postfix/smtpd[28105]: disconnect from unknown[x.x.x.x]

but i want to allow every mail coming from this mail3 IP mailserver (or better for the full network range we have in the data center) so that the receiving mailserver is accepting every mail from them)

5

Re: disable sender reject for allowed hosts

I managed to get it working by setting "yes" to "no" for

smtpd_reject_unlisted_sender = no

but now a possible attacker can send mails to our users under a different "trusted" mail-address which comes not from our mailserver.
can i restrict this to only one external subnet which is allowed to do this kind of mails? (refer to my last post)

Thank you for your help!

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Re: disable sender reject for allowed hosts

martinseener wrote:

Recipient address rejected: User unknown in virtual mailbox table

As shown in the error log, Postfix will check recipient address in SQL/LDAP database first. If recipient doesn't exist, it rejects this email.

Does mseener@example.org exist on your server?
Maybe you want to disable recipient check or just don't reject email before queue?

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Re: disable sender reject for allowed hosts

hi, i dont want to add every possible sender from our datacenter.
is there a way to allow every sender coming from a specific IP Subnet of mailservers? therefore, yes i want to disable this check for a well-known IP Range of Mailservers (those in our data center).

so i can reenable smtpd_reject_unlisted_sender = no to yes again.

How can i manage this?