Questions tagged [postfix]
Free and open source mail transfer agent (MTA) that routes and delivers email. When asking about postfix problem, please include the relevant maillog lines and output of the following command: `postconf -n` (non-default content of main.cf) and `postconf -M` (content of master.cf)
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Specific incoming mail to postfix rejected by sslv3 alert bad certifica te:s3_pkt.c:1493:SSL alert number 42:
I have postfix running on mail.myserver.com for the past 15+ years, successfully receiving and sending mail. All certs are fully valid using Let's Encrypt. I can verify that they are fine using ...
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postfix transport maps not working correctly with lmtp
I am trying to get mailman 3 running with my existing postfix server on another host in the internet. I think I am quite far, but for some reason, postfix does not correctly send mails for mailman to ...
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How do I view mail (postfix?) configuration settings?
I inherited a server that is mailing status messages via an external mail-server. It runs crontabs that run scripts that send mails. Example (simplified):
echo "disk free status 10GB" | ...
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PHP PEAR Mail STARTTLS failed error 220 with postfix
I'm running postfix with dovecot. I'm trying to use the PHP Pear Mail package to send e-mails, but I can't get it to work. The error I get is this: authentication failure [SMTP: STARTTLS failed (code: ...
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How to change the sender / from field using Postfix as SMTP relay server to relay to MSO365 mailbox
My company have set up an Ubuntu 22.04 Server to act as an SMTP relay server to relay messages to our Exchange online mail server.
A user account [email protected] has been setup on the Exchange to be ...
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78
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postfix issue with combined check of sender-domain, login and IP Whitelisting
I would like to have a postfix that allows mail relay to a relayhost when
a) the sender-domain is allowed
and one of:
b) the sender has authenticated
c) the client has a IP whitelist entry
my current ...
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1k
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How to get both ECC & RSA certificates from Let's Encrypt for Postfix?
Let's Encrypt has started issuing ECC certificates by default since Certbot 2.0. This is not a problem for modern web browsers, but Let's Encrypt certificates can be used for other purposes than HTTPS,...
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Postfix - SASL Cyrus saslauthd authentication failed
Goal: Configure smtpd to authenticate connections by using postfix, cyrus, saslauthd, pam and mysql.
Investigation
Authentication via courier-pop3 & courier-imap using mysql works
saslauthd ...
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2
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391
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Forwarding email message breaks DKIM
I have problem with postfix, DKIM and forwarding messages. In almost every article about DKIM I’m reading that “if I do not modify any fields in message header, DKIM signature should still be valid ...
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110
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Something sends email to OpenDKIM even after purging it
I can't send email from my server using Postfix. The /var/log/mail.log has:
postfix/local[1803]: 59367CDB9: to=<[email protected]>, orig_to=<opendkim>, relay=local, delay=0.03, delays=0....
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Dovecot - rcpt [email protected]: Failed to initialize user
I have an SMTP server:
Dovecot as its IMAP server
Postfix as its MTA
OpenDKIM to sign the emails.
When I send mail it throws this error:
Jan 01 10:46:01 example.com dovecot[211047]: lmtp(219823): ...
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263
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Postfix doesn't send mail; example.com loops back to myself & Connection timed out
I have Postfix on Ubuntu 22.04. I can only receive but not send emails.
I have configured Postfix using How To Install and Configure Postfix on Ubuntu 22.04 tutorial from DigitalOcean.
sudo tail -f /...
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3
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238
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Unable to login as admin with Postfix in docker container
I have tried to setup Postfix as a test server to allow TDD-tests to run with email verification on a local email server.
This is my yml file for docker compose
postfixadmin:
image: postfixadmin
...
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2
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Add Multiple Subdomains In Signing Table And Key Table Opendkim
I need some major help adding multiple subdomains in the signing table and key table for opendkim without listing them one by one.
If I have 50 subdomains I want to add, it will take me forever.
I am ...
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150
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Failed to send SMTP email with PowerShell and Postfix SMTP relay
I tried to correct some errors with a PowerShell script with Send-MailMessage() that sends an email via a Postfix SMTP relay, but it returns this error:
error PowerShell
I found that I should add this ...
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153
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Postfix to not delivery mail to domains using another mail server
I am configuring a hosting + mail setup. I have one server for hosting websites, and one for the smtp/imap/dovecat server.
As far as I researched, the only reasonable way to allow my customers to have ...
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2
answers
485
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Opendkim can not find domain key (No such file or directory)
I am building a mailserver with postfix, dovecot and opendkim using Ubuntu 22 LTS. Everything worked fine in my dev environment (same setup as far as I checked), but when I deployed it live, opendkim ...
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1
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131
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Postfix replace string in Received: header
I am using Postfix, and trying to replace the string "14.03.0513.000" with "15.20.7091.31" in a "Received:" header similar to the one below:
Received: from srv1....
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39
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Postfix - Only allow relaying when sent from local user
At the moment, our Postfix + Dovecot mail system has two types of users: those with a full account and those with only a forwarder.
Users with a full account are in the virtual_aliases table pointing ...
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139
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Why dovecot use "postfix_accounts.users" to retrieve mail user information after username/password auth?
I had set up a mail server in my Rocky Linux 9.1 that comes with postfix, dovecot and mysql (refer to https://computingforgeeks.com/how-to-setup-mail-server-on-centos/).
Every thing is updated. (...
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Can iptables state miss some packets?
I tried to setup the iptable rules for MTA. As this MTA is meant only for receiving the emails I allowed INPUT packets from any to destination port 25 with state either new or established, and allowed ...
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Sasl connection refused
i am trying to run a selfhosted mailserver using postfix and dovecot.
firstly i configured only postfix without dovecot and that worked fine but i wanted to use a mail client so i installed dovecot to ...
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169
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How can set the order of name servers in LINUX?
This question is in context with the DNS queries by postfix MTA in Ubuntu OS. The issue I am facing is that I have two name servers one internal and one external. External DNS name server is added in ...
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Postfix server seems not to act properly on smtp response codes, it keeps retrying for 5 days after 5.1.1 permanent errors
Recently we've got into trouble with a big receiving MX system (got temporarily blacklisted). After some discussion with the postmaster who was extremely helpful, he showed me his log entries with ...
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150
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what comes first smtpd milters or cleanup in order of filtering in postfix?
Based on the documentation of the postfix (as stated here: 'https://www.postfix.org/SMTPD_PROXY_README.html') the smtpd milters should be used to filter the emails first and then the cleanup service ...
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145
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Is possible to use a DKIM-Proxy to signing emails requested from another application?
I using an application to send emails, written in golang which use net/smtp as SMTP Libary, however that lib provide no support with DKIM signing, but using a sendmail command, for example, the DKIM ...
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Milter Application Error Postfix Email Server
I am trying to sign the emails on my email server with opendkim but I am running against an error that I just can't seem to fix. The error I am getting is: warning: milter local:opendkim/opendkim.sock:...
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239
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postfix + spamassassin check SPF from the email headers
I have postfix + spamassassin.
Spamassassin suppose to check the SPF of the sender, but I received following spam:
[email protected] = this is the email on my postfix
Return-Path: <leonah@betterway....
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postfix: remap user credentials for relayhost
I've been trying to figure out how to have postfix remap the username for an SMTP relay host similar to how fetchmail does for the inbound email.
In my fetchmailrc I have something that looks like ...
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140
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POSTFIX smtpd relay depending on sender
I am using Postfix on a server mx1.domain1.com to relay e-mails for domain1.com as well as other domains, domain2.net, and domain3.org, which are hosted on the server (domain1.com). In addition, mx1....
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Different spam filter method for sasl-auth clients?
Using a standard Ubuntu postfix setup (Ubuntu 22.04), I would like to filter mail as follows:
Incoming submission and smtps (the vast majority of mail): SPF and RBL checks (I'm using policyd.pl), ...
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100
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Dovecot not receiving mail while making use of vmail
Below is my current vmail configuration.
auth_mechanisms = plain login
auth_username_format = %n
protocols = imap lmtp
# Search for valid users in /etc/passwd
userdb {
driver = passwd
...
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2
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102
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In Postfix, Should SSL FQDN Matches with myhostname or mydomain field in /etc/postfix/main.cf?
Quoted from the documentation:
myhostname
The internet hostname of this mail system. The default is to use the fully-qualified domain name (FQDN) from gethostname(), or to use the non-FQDN result ...
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Warning: you may need to increase the main.cf smtp_destination_concurrency_limit - but it is set?
We have a huge delivery of emails right now and emails are not delivered as fast as I think they would:
In the mail log (Postfix v3.4.13 ) I see the following message
Dec 8 14:34:28 s29 postfix/qmgr[...
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postfix sending only short messages ( emails ) but not long messages?
when I am sending a short email from "[email protected]" or any other email acc , the message is received well in the inbox of Gmail , hotmail etc , but if I send the message again with long ...
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How to upgrade postfix/dovecot/spamassassin/postscreen email server from Ubuntu 20.04 to Ubuntu 22.04?
I am running an Ubuntu 20.04 based LEMP Email server running Postfix, Dovecot, Postscreen, and SpamAssassin. I built the server using this Linuxbabe Guide, and followed the instructions and every ...
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216
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How to set up the relayhost to send emails to other external SMTP servers using PostFIX?
I am currently configuring an SMTP server on OCI but have some doubts. I would like to send emails with my domain to external servers such as GMAIL, OUTLOOK, and others.
I had configured the "...
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Spammers are using my mail server to send out emails
Lately spammers are using my mail server to send emails to different addresses.
For example, a colleague of mine received an email that was supposedly self-sent (it was not).
Looking at the ...
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Issue with 'delay_reject=no' and smtpd_helo_restrictions in Postfix
In Postfix MTA, I have set helo and client restrictions with the DISCARD policy. But since setting delay_reject=no I am getting this error just after connect from for some clients (don't know if they ...
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152
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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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99
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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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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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2
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46
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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 ...
- 203
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172
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Postfix rejecting my email from a "Contact Us" form, with "SMTPRecipientsRefused"
I made a "Contact Us" form in Django, and the Django part of it seems to be working. But sending of the email it generates fails with
SMTPRecipientsRefused at /contact/
{'[email protected]'...
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2
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991
views
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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2
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238
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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 ...
- 203
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241
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postfix as relay - send to non local domain restrict by ip
we are moving from an old symantec messaging gateway to a debian/postfix machine.
rules in symantec are these:
-from local domain to the same, accept from all then relay all to outlook.com server.
-...
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290
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What does "warning: hostname domain.com does not resolve to address" actually mean?
Variations of this warning show up many times in the Postfix logs:
warning: hostname 107-174-39-133-host.colocrossing.com does not resolve
to address 107.174.39.133: Name or service not known
I'...
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