Questions tagged [smtp]
SMTP is the Simple Mail Transfer Protocol, the most recent standard of which is defined in RFC 5321. It's the Internet standard for sending and receiving email.
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Why do certificate CNs not match the hostnames provided in MX records?
I'm the author of checkdmarc, an open source CLI tool for checking DMARC and other email security standards. One of those checks involves testing if the mail servers listed in a domain's MX records ...
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How to interface with Postfix `non_smpt_milter`?
After many hours attempting to configure OpenDKIM with Postfix and having no luck, I have come to the conclusions that:
I cannot get OpenDKIM to work
I am not able to find a suitable out-of-the box ...
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send email using multiple domain emails using main domain postfix smtp server
I have a domain with postfix for SMTP server, eg EM-NAME.DOMAINNAME.COM
We are sending emails in bulk from domain email [email protected]
I am trying to send emails on behalf of my ...
2
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SMTP Port 25 Issue on Nginx Mail Proxy
I set up an Nginx mail proxy server and configured it to distribute to several mail servers as a front-end server. However, I need to open port 25 in the configuration; otherwise, I cannot receive ...
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SMTP - How to send mail as @example.com when example.com cannot be used as source server/IP
I have run into a bit of an issue when attempting to set up a mail system where the parent domain, example.com, already has A records and a web server as well as many clients utilizing the parent ...
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Set custom ingress port on google cloud run
I'm trying to deploy an SMTP Server on google cloud run and so far I haven't been able to figure out how to attach a TCP/UDP Load Balancer to the back end.
Is there a way for my Cloud Run application ...
google-cloud-platform
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Attempting to set up an exim4 SMTP only server that can send out messages from two domains
I am attempting to set a STMP server that can send out messages from two different domains
Adding this line to the the config file (update-exim4.conf.conf)
PRIMARY_HOSTNAME = $sender_address_domain
...
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Gitlab SMTP Configuration
I am new to Gitlab. I configure SMTP in Gitlab that looks like,
{:authentication=>:login,
:user_name=>"My Email",
:password=>"Email ...
1
vote
1
answer
40
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Postfix connection timeout to all servers
I have Postfix on an Ubuntu server.
postconf mail_version
mail_version = 3.6.4
Every email i send to any recipient ( tried gmail , hotmail and yahoo ) , is stuck in the queue
(connect to alt2.aspmx.l....
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2
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Abuse of Abuse reporting system / Feedback loop by spfbl.net
We are getting below abuse emails from Abuse reporting system / Feedback loop by spfbl.net
Can someone explain how are these even valid Abuse emails in any sense at all, because they are clearly being ...
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How to configure sendmail to forward all mail to another host?
I have an Ubuntu host with a public DNS A record on example.com. The sendmail program is installed on the host with the sendmail package.
The MX records are set up to use Google Workspace, per Google'...
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2
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How can I mitigate a flood of inbound emails that look legitimate to filters?
I have a mail server - postfix, amavis, dovecot. Currently one of my inboxes is being flooded with random email from all over the globe. It's like someone signed me up to 10,000 newsletters all at ...
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wordpress + wp mail smtp = email not sending with php mailer
I have a docker wordpress website with WP mail SMTP plugin.
I selected the default PHP
Emails are not sending. sending test email gives a 504 timeout error
php sendmail is installed
Dockerfile for ...
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Postfix replace in body by adding CR
I'm trying to configure Postfix body_checks function in order to add a CRLF when an end of attachment is detected using this:
/(.+)--$/ REPLACE $1--\r\n
The regex is correctly applied but the \r\n is ...
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How to change the sender address using mailutils and postfix?
May 27 14:19:33 localhost postfix/qmgr[21793]: 87FD870AD12: from=user@localhost,
size=398, nrcpt=2 (queue active)
May 27 14:20:03 localhost postfix/smtp[22591]: connect to
mail.rungel.net[95.168.160....
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2
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554 5.7.1 Relay access denied - cant send mails
I tried to upgrade debian from 10 to 11 and the everything got messed up. Im trying to fix postfix. I can receive emails but cant send. I get the error "554 5.7.1 Relay access denied"
My ...
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How to add your own private keys to postfix configuration for DKIM without opendkim or the likes of it?
I have generated the keys locally through openssl added key.pub to the DKIM DNS txt Record but how to add it to postfix withouth any other tool.Is there any connfiguration parameter where the file ...
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Cant restrict SMTP connection by IP in Amazon SES
I use Amazon SES to send transactional emails (using SMTP connection) from my app and I wanna improve the credentials security by restricting access from specific IPs.
I've created an IAM Policy for ...
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Even though I got full score in mail-tester, gmail still gives an error of IP address not being authorized when using sendmail
I'm using sendmail and I passed the DMARC, SPF and DKIM
but when I send an email to [email protected], I get this below error:
50-5.7.1 The IP you're using to send mail is not
550-5.7.1 authorized to ...
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1
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SMTP Server: Postfix w/ Dovecot - how to configure the allowed username + password?
I seek a Linux-based SMTP server.
I've read tutorials and specs regarding Postfix SASL with Dovecot, though I can't find how to configure the list of username and password which are allowed to send ...
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How can I make MIAB automatically copy all mail sent via SMTP into the sent folder of the sender's account?
I run Mail-In-A-Box on my mail server and one of my clients is using a specialized application to send messages via SMTP from their account on my server. When they used their own Gmail account to send ...
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All containers on a server fail to send SMTP requests, the rest works fine
We have a VPS with several services in Docker containers, on top of which, another Docker container runs a Traefik reverse proxy.
Last Monday morning, all the services running on that server failed to ...
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3
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273
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Postfix sending duplicate emails under different userid's, how to fix?
I can't find a reason for it in the postfix settings, but duplicate emails are being sent, under different uid's. Looking at the email headers, they have unique ids, and each with a different Postfix, ...
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1
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128
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Postfix - can't limit active queue
One of the destinations I send email to has unusual performance characteristics. The active queue can fill up with messages for this domain, blocking sending to other domains. I want to limit the ...
- 23k
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2
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58
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Cannot get Exim to verify DANE for remote smtp
I am trying to configure Exim to try DANE before deciding to deliver unencrypted mail to remote hosts.
My general Exim configuration has: dns_dnssec_ok = 1.
For the dnslookup router: ...
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0
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authenticate users in smtp relay server exim4
I'm configuring relay SMTP server for sending email alerts from my local network. I need to send emails alerts from services witch run on my servers. And I need to authenticate it: each service should ...
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0
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postfix MTA seemingly benign I/O Error : postqueue fatal: output write error: Input/output error
I am getting the following message in my syslog exactly every 30 seconds. Everything is working but words like "Fatal" and "Input/output error" cause me an inordinate amount of ...
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VM behind nat on Proxmox cannot reach port from internal network
The issue is that I am able to reach port 25 from outside (public internet) to the specific machine in the local network behind NAT, but cannot reach to port 25 on public machine e.g. hotmail-com.olc....
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248
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How to install sendmail client only, without the MTA?
Is there any way to install the sendmail client, only, without installing the sendmail MTA at all?
What I mean by this is the sendmail -t command that is frequently used by processes such as cron to ...
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Email Sender Identities / Single Sender Verification
I have a self-hosted web service and one of its features is allowing customers to send emails to their customers. Currently we send these emails on behalf of our customers by setting:
from: mailer@...
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53
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How to send email from smtp server1 to smtp server2 (Postfix) via client?
How to make server1 with postfix can send email to server2 with postfix by redirecting DNS query to it (type forward). These servers are on the same local network. Server1 is to receive a non-...
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128
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Changing sendmail HELO/ELHO header in docker container
I have a Debian 11 docker container in which sendmail v. 8.15.2 is installed as MTA. Unfortunately spamhaus.org blacklisted the host IP due to the HELO header of mails being sent from this container ...
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118
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Postfix/Dovecot fails to send emails "SASL PLAIN authentication failed" - no further message
I have been all around the houses trying to configure Postfix and Dovecot so I can send through my domain from Gmail, which as far as I know is simply Gmail acting as a regular SMTP client talking to ...
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Telnet SmarterMail: 550 This is a submission only port. You must authenticate before sending mail
I have a "newer" server running Windows Server 2019 and I installed Smartermail FREE Edition so I could send mail via PHP/CDONTs from contact forms to my email address.
I tried matching the ...
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If a lower priority mail server only serves code 450, will sending servers on retry use a higher priority server?
I had a backup mail server eat a bunch of messages and I want to just configure a simple server to send 450 for all messages.
However, I'm not sure this is a good idea because if the sending servers ...
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3
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Outlook getting spurious SMTP errors when connecting to Linux dovecot mail server
I'm running a mail server for about 30 people. I have had zero issues with it. But last week, several users began reporting an error in their email client, Outlook:
Checking the server mail log ...
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199
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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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1
answer
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Why Google SMTP MTA's are not sending STARTTLS command
I'm a software engineer that wrote my own SMTP delivery agent. I recently added the STARTTLS support to my software and I was doing some testing, when I noticed that Google's SMTP transfer agents are ...
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How to use NGINX as legacy SMTP proxy to new SMTP system?
We have some very old radio equipment in the field which uses SMTP to notify us of failures. Unfortunately this equipment does not support modern SMTP authentication methods (SSL, etc), and can only ...
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Original DKIM signing is not sent when using SMTP relay
We are using a VPS (ubuntu 18, postfix) to send mails for multiple domains hosted on a server (AlmaLinux 8). For example from the domain "domain.com".
VPS is maildomain.com
Hosting server ...
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0
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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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1
answer
157
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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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0
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150
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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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1
answer
148
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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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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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Is opening SMTP port with default Sendmail config safe?
My self-hosted web app (Ubuntu VPS) needs the ability to send noreply@ notifications to users when something goes wrong. I don't really need the ability to receive emails but I would like to comply ...
0
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1
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340
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Can I generate and log output alerts for SMTP traffic using Suricata 7.0.2?
I have Suricata 7.0.2 IDS installed on a Linux Ubuntu 20.04 virtual machine. In my virtual environment, I have two virtual networks. In the first network, I have a mail user agent (Attacker) that ...
0
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0
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174
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PAM failing to authenticate all users from one domain in dovecot
I have installed a mail server using Dovecot + Postfix, and it always worked correctly.
Recently I installed a new domain example.com and a user [email protected] for that domain in the mailserver ...
0
votes
2
answers
778
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mailpit / kubernetes: SMTP sendmail cannot connect - telnet works fine
kuberntes setup:
mailpit service + deployment
(ingress works, I can connect to the UI)
---
apiVersion: v1
kind: Service
metadata:
name: desideria-crm-mailpit
namespace: desideria-crm
labels:
...
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