Questions tagged [email-server]
Refers to the hardware or software that make up a server dedicated to sending and receiving emails. Many popular modern email servers bundle other functionality for contacts and calendaring along email delivery.
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What is meant by "Message sorting optimization records" in dovecot index?
Dovecot documentation here "https://doc.dovecot.org/developer_manual/design/indexes/index_file_format/#main-index" says that "Message sorting optimization records" are stored in ...
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What is difference between uidvalidity and list index file in dovecot?
Dovecot's document notation says that uid-validity file store IMAP UID to filename mapping but it also says list.index file also store same. If it's so what is need of two files.
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In postfix can I mention sender access map in client restriction?
It's a question out of curiosity rather than necessity. What should happen say I place sender access map inside smtpd_client_restrictions and also place client access map in smtpd_sender_restrictions ...
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In postfix how parent_domain_matches_subdomains helps rejecting mail for subdomains?
Based on the standard configuration given in https://www.postfix.org/STANDARD_CONFIGURATION_README.html#firewall the parent_domain_matches_subdomains = debug_peer_list, smtpd_access_maps should help ...
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How OpenDKIM decides which emails to sign?
In OpenDKIM, what domain does it consider to use when comparing to internal hosts? Do it consider the domain of Return-Path (i.e. envelope MAIL FROM's domain) or header From or HELO's domain.
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Why is it advised to disable relayhost when hosting mail server behind firewall?
I am trying to setup an MTA. While reading documentation I came across "Standard Configuration" for Running Postfix behind a firewall.
I am confused on this part:
IMPORTANT: do not specify ...
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Can I log when the message arrival rate exceeds the message delivery rate in postfix?
I am trying to implement a MTA, on reading documentation of the postfix I found a parameter 'in_flow_delay' whose description in sort says 'Time to pause before accepting a new message, when the ...
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What is behaviour of opendkim while verifying an email with multiple dkim signatures?
I am trying to implement DKIM verification using Opendkim and postfix. The doubt I am struck by is what will happen if the email has more than one DKIM signature and one of them fails (as like failed ...
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What difference does it make to implement a feature as policy service vs as milter in Postfix?
I am trying to implement MTA using Postfix. I am struck at how to implement standard services like SPF, DKIM etc. as well as some custom services. They can either be implemented as policy delegation ...
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What are typically the headers which I should oversign?
I am trying to setup MTA using Postfix and using opendkim for dkim signing. When I went through opemdkim documentation it have a field which is named 'OversignHeaders' document describes it as: "...
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What does "--[no]subdomains" option in opendkim-genkey mean?
Based on the documentation --nosubdomains "Disallows subdomain signing by this key". But didn't we need to create separate DKIM records for subdomains regardless?
Please correct me if I am ...
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What is difference between using smtp vs relay transport type in postfix?
I am trying to setup MTA which should submit different intranet mail gateways based on the recipient's domain. For that I thinks transport_maps in postfix should be setup for selective domains; if ...
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How to restrict based on combined usage of sender email and client ip address in postfix?
I have a MTA (postfix) with sasl implemented. I want that for a subset of users I can map their email address to a particular range of ips (separate for each email user). If a user tries to send email ...
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Dovecot: Import from /var/spool/mail mbox to ~/Maildir
I've just migrated a personal mailserver from Courier MTA setup to a Postfix/Dovecot one. I thought I had it all worked out, but after I updated the MX record I realized Postfix was dumping mail into ...
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How to bypass postfix milters for certain users?
I am trying to setup an incoming MTA server using postfix. I have specific requirements that emails for some of the users should not go through the milters. Is there any way this can be done in ...
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Too many connect from unknown postfix
I am trying to set up an incoming email server by using postfix as MTA the issue I am facing is that there are too many 'connect from unknown' lines in the log. Can anyone help can I debug this issue? ...
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Permission problems with uWSGI and Modoboa
I have run a manual installation of Modoboa (https://modoboa.readthedocs.io/en/latest/installation.html#manual-installation), which runs a webapp in uWSGI. I moved the static content to /var/www/html ...
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OpenDKIM gets installed without RSA-SHA256 support
I compiled opendkim from source with the following commands:
mkdir /opt/opendkim
cd /opt/opendkim
wget https://sourceforge.net/projects/opendkim/files/opendkim-2.10.3.tar.gz
tar -xzvf opendkim-2.10.3....
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Perm Error sometimes not know if it sender issue or receiver issue
I am facing the problem, sometimes from the sender , i am able to receive the mail, sometimes it block, getting the error ---
Sender: @dekra.com
Recipient: @autodienst-hoppegarten.de
working header: ...
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Configure postfix virtual transport to deliver mail to arbitrary (local) addresses
I'm using Postfix in a very niche application with no inbound or outbound SMTP connectivity (other than via the loopback interface).
I would like to configure the postfix virtual transport to deliver ...
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dovecot maillog does not run or does not update after error appears
Dovecot maillog doesn't run after receiving an error like this, is there a solution to handle it? for email to run smoothly only maillog doesn't work, I've tried restarting postfix & dovecot, and ...
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Dovecot certificate is empty
I configured a Mail server with postfix, dovecot and mysql from the documentation.
When I add a mail address in Outlook, it refused.
I tried everything what I can find, but nothing helps.
Can somebody ...
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What are the correct settings to enable TLS between Postfix and Dovecot via LMTP?
I am trying to get Postfix to forward mail via LMTP to Dovecot. This works fine when TLS is turned off in the settings on both sides.
Once TLS settings are enabled, Postfix connects via LMTP and ...
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How to have different postfix options based upon destination email address
I need to configure postfix in such a way that the options used vary dependent upon the destination email address. For example, I might have destinations such as [email protected], [email protected], user@baz....
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Amavis outbound mail filter for Postfix?
Running Postfix on Ubuntu 22.04, I'd like to make sure all outgoing mail originating from the server (eg mail forms on websites and stuff) is filtered for spam and malware. I'm using Amavis, which is ...
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Does LMTP support authentication?
Scenario:
A Postfix Server runs on a VPS with a hosting company.
A Dovecot IMAP server runs inside the office.
We want Postfix to push mail it receives to the Dovecot IMAP server, using the least ...
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Postfix - limit outgoing messages sent by one specific user
I want to limit outgoing messages to 5 per hour for a single user. It should then queue any additional messages during that hour to be attempted for delivery later. All other users should not be ...
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Postfix Trigger script when E-Mail was Sent
This is my first Post at serverfault.
I hope someone can help me.
My setup looks like this:
I have a RabbitMQ where emails are queued.
I've written a small Python tool that retrieves one email at a ...
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Postfix seems to be running and listening on the public network interface, but external clients cannot connect?
I'm setting up a new Postifx server on Debian 12. I've installed the Debian package and confirmed that Postfix is running, and is listening on ports 25,465, and 587.
Postfix is running and there are ...
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With postfix, how do you setup SASL with dovecot to receive SMTP mail and cyrus to authenticate?
I had a static IP address and setting up my mail relay was as easy as:
mynetworks = ... <static IP address> ...
(and of course authorize all incoming mail from mynetworks).
Now that I do not ...
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Dovecot process synchronization for duplicate email detection
We have a dovecot server version 2.3.16 with sieve duplicate extension enabled to detect and discard duplicates. We have duplicate routing in Postfix virtual_aliases file which causes duplicate copies ...
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Postfix+Dovecot: filter email with certain `To:` address
I have a postfix+dovecot email server. There is one mailbox that was used by the Procurement department in many online shops and the address got disclosed and included in a spam list.
I would like to ...
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A Non-MX mail server + Google Workspace, is this viable?
I have a domain (example.com) configured for sending and receiving mail using Google Workspace. I need to launch additionally a separate (own) mail server. Switching completely to the new server is ...
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Should HELO, MAILFROM and From use the same domain?
I configured a mail server a couple of times before and I believe back then I thought
that the answer is "yes."
But I'm about to configure another one, and it seems that I was wrong. Let's ...
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How to properly filter emails through EXIM system filter?
My server recently encountered a large volume of incoming spam messages. For each message, Exim agent generated a message with the following content for the sender:
"Mail Delivery Failed: ...
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Can I Force Implicit TLS Connection For Port 587 On Postfix?
I have read many articles saying port 587 by default is explicit TLS. This means it's STARTTLS. It asks the server on an unsecured connection if TLS is supported and if it is, it continues with an ...
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Wrap plain text mail in html
we use Postfix as MTA to send our mails from our system. Unfortunately we have an old persistent system which we cannot change, which sends mails to our customers in plain text format. I would like to ...
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HCL Notes internet address not found in the secondary address book
I have an issue which I can't get resolved. I hope you can help me out.
I have setup a secondary NAB in HCL Notes/Domino v12.0.2 which is mainly being used for web users to authenticate. I have setup ...
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Postfix: How can I handle incoming mail for a single address, not the entire domain?
I've gotten my employer to configure the company-wide Exchange server to forward [email protected] to [email protected], a host I control. So far, so good. My Postfix configuration ...
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Simple solution to archive dovecot/postfix emails to second server nightly for long term storage with roundcube access
Our email server has ~150 email accounts containing material that cannot be deleted for 10 years. Some accounts are heading towards 10gb of data so I'd like to setup a nightly archive process that ...
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Deliver mails in Maildir in /var/spool/mail with Postfix
I search for hours without finding the solution and it drives me crazy.
Is it possible to ensure, without using Procmail, that Postfix delivers emails in the form of Maildir {cur,new,tmp} in
/var/...
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Receive notification whenever someone marks email as spam POSTFIX
I have created a mail server using Postfix. I have added a 1x1 tracking pixel to track email opens.
I would like to receive a notification either on an http endpoint or my email address whenever ...
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NGINX Mail proxy IMAP Auth Errors
I need some help getting NGINX to perform IMAP authentication as a reverse proxy into Postfix Mail server on-prem. I am seeing the tracking on my POSTFIX mail server, but IMAP continues to fail. seems ...
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Which IP address in email headers should I ban to block spam from this source?
I got scam email from zcsend.net. This time the sender address is faked. I need to use Fail2Ban to ban messages from the same origin. However, there are many addresses here in the headers. Which one ...
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How to add a PTR (Reverse DNS) on Vultr? Do I need to contact them?
I have set up a Postfix Dovecot email server on my Vultr. And I'm getting following message from Google:
gmail-smtp-in.l.google.com said: 550-5.7.1
Our system has detected that
550-5.7.1 ...
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Dovecot says user does not exist although it's in MariaDB database
I use a MariaDB to store users for Dovecot 2.2.10. The Dovecot keeps giving "Disconnected unexpectedly" errors, and I can't find a reason. Is there anything I could look at?
Mail logs
Aug 29 ...
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Linux port 25 is not working, and postfix unable to establish external connections at port 465, internal connection works with issues
I guess these are two typical issues, at least first one is. I'm trying to configure postfix dovecot on CentOS 7.
First, the port 25 is open, but it is not accepting any outer connections.
The ...
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Two mail server installs (for two domains) on Windows VPS with one IP?
I'm starting with 1 IP address and the supplied mail server software license supports only 1 domain.
I'm now adding a second domain to the VPS on the same IP address. There's a LARGE increase in cost ...
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60
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Adding MX record
I would want to achieve the following: I have acquired a domain name, and I would like to add a website and a mail server for this domain. I have: 1 Domain name, 1 private Ubuntu server with IP, 1 ...
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Proving Email Origin through Mail Header
A supplier appears to be have been a victim of an server breach (though they are denying this and bring the point of my question).
This has then caused the directors of our company to make a payment ...
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