Questions tagged [smtp]
SMTP is a protocol built upon TCP/IP, used for outgoing email transmissions, and email relaying. It uses ports 25 (clear) and 465 (SSL) by default.
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Light program (mini MTA?) for system mail (only sending/relay via external server with unattended-upgrades, cron, smartmontools, etc.)
I've come across different names in different places: Light MTA, Remote MTA, Smarthost, etc.
Generally, I do not want to install a full-fledged mail server (such as sendmail, postfix, exim), but only ...
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How to configure Linux (debian 11) as an SMTP Gateway with authentication
Hope you are all having a good friday.
The situation is - I have a local MS Exchange Server, which currently has a windows based server in the cloud that I'm using as an SMTP relay - it works great ...
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Postfix delivers messages locally despite configuration for discovering external agent
A small node operates several web applications attached to a domain.
The same domain is used for mailboxes, hosted off site by a commercial service.
On the name server operated by the registrar, A, ...
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OpenSMTPD: Mails that should be in root user's mbox is in default user's mail box
So I have setup an OpenSMTPD server on my OpenBSD VPS.
I have specified the aliases file path and configured action "local_mail" to forward the mails to specific users based on their ...
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timed out while receiving the initial server greeting
I'm trying to host a postfix mail server.I have a box with a fixed IP and also a mx record and spf record that link my box IP to my dns record. I can telnet to alt4.gmail-smtp-in.l.google.com 25 but ...
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Unable to receive email using postfix
I am playing with the postfix to send an email from azure pipeline through a task. I use Ubuntu 20.04 in the pipeline. Here is the task I created where I have simple bash script.
sudo apt install ...
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"mailx -a x.txt ..." hangs, while "cat x.txt | mailx..." works
As described in the subject, mailx -a somefile.txt -s "blah blah" [email protected] hangs, while emails sent via cat somefile.txt | mailx -s "blah blah" [email protected] ...
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Postfix SMTP relay to Office 365
i trying to setup Postfix SMTP on my CentOS 7.8 i following https://www.middlewareinventory.com/blog/postfix-relay-office-365/
and got stuck on this error
May 30 21:36:28 pbx12 postfix/qmgr[15174]: ...
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Restricting list address who can send email from server
i want to restrict only a specific list from my Ubuntu system running Postfix to send emails,
of course i could receive external email ( sender/recipient)
supposing my domain name is tt.net
here's ...
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mailx works, but mutt has stopped working
RHEL 8.4
I've got a script (run via cron, if it makes a difference, though the same problems occur interactively) which sends an email (through a corporate smtp server) based on several conditions.
If ...
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How to configure MX on Postfix
I'm trying to configure Postfix version 2.10.1 on my server under CentOS 7, which relays emails sent to the mail server, but I have a problem setting the MX. Indeed, in my configuration, the MX used ...
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Mail relay allowing "internal" senders to mail only to our own domains unless they come from certain IPs or authenticate
Scroll to bottom for configuration snippets
I have NewInternalMailserver being set up to relay for internal applications that have been hard coded for InternalMailServerURL.
When mailing "our&...
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Auth error when sending mail through Postfix with SSMTP (local server)
I'm trying to send mail from a banana pi running SSMTP to a raspberry pi running dovecot/postfix.
I used Thunderbird to login to my mail server it showed three times saying "Unable to log in at ...
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telnet localhost 25 vs telnet localhost 587
I install a postfix with the following postconf -n:(however I changed my domain to example.com)
alias_database = hash:/etc/aliases
alias_maps = hash:/etc/aliases
append_dot_mydomain = no
biff = no
...
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NOQUEUE: reject: Helo command rejected: need fully-qualified hostname
I am running 3 x Win11 and 1 x Win10 all with Office 365 Outlook. 3 of the Outlook clients connect to a postfix/dovecot server just fine on my home NAT, and can tunnel through my router from the ...
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How to mailx working with Content-Type: text/html
I've to send a HTML file with mailx command but when I receive the email with the mark up code showed like this :
<HTML><HEAD><TITLE>Title One /TITLE> <STYLE> body { ...
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How to identify which URL is attempting to access SMTP from browser
Opening a web page attempts to access SMTP server in the network. I am not able to identify exactly which URL is attempting for the same. Due to nature of the work, many tabs are open in the browser.
...
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Which domain is HELO checked against with rDNS? Mail server's domain, even if different from the sender's domain? Or the email sender's domain?
I run a small webserver that hosts a handful of domains which I use for personal and testing purposes. I want to set it up as a mail server as well, and I'm trying to understand the rDNS lookup that ...
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Unable to Open SMTP Port (25, 587) on Vultr
I'm using Vultr for Web Hosting and according to them they have unblocked all SMTP Ports (25, 465, 587, 2525). Now after setting up apache server and installing Postfix, Dovecot and SpamAssassin when ...
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Trying to use sendmail to a relay that runs on port 25, with no luck (bad dh value)
In my organization, I have a GitLab server that needs to have the ability to send emails. My organization has a mail relay that we must use to send email out to users. I have a RHEL 8 box with GitLab ...
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Any email clients for Linux with capability of sending an email multiple times to mail-list recipients individually?
Any email clients for Linux with capability of sending an email multiple times to mail-list recipients individually?
Up to 30 recipients, if it is important.
P.S. No, python script does not work ...
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AnsibleTower sending every n-th notification
I have automated some stuff using AnsibleTower (4.1.1, RHEL8 4.18.0-372.19) and it works as expected. Yet when it comes to sending email notifications, there is something I cannot explain. The Tower ...
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OpenSMTPD: MX lookup for relay host
I'm trying to figure how opensmtpd can be used to relay email using a specific host, which should be figured with an MX lookup.
Let's say that i have my MX record for internaldomain.server.lan.
This ...
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Modifying specific SMTP messages while in transit using a Postfix Filter
I'm looking to set up a simple Postfix server that can modify the content and recipient of some specific SMTP messages.
I'm not super confident in my approach so far and feel like I missing some ...
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How can I write a command into a subprocess?
Currently, I am working on a project where I use telnet to netcat to send an email message within my university.
I am trying to make the process automated but my script can't seem to enter in any ...
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Sending an email to myself using Mutt results in SMTP session failed: 554 5.7.1 You are sending spam
I use two OpenBSD machines (notebooks) that have configured mutt clients.
One of them has OpenBSD 7.0 on it with mutt version 2.1.3, while the other runs OpenBSD 7.1 with mutt 2.2.3 .
Both of them use ...
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Postfix rejecting outgoing emails because of "Relay access denied." | "generic_checks: name=reject_unauth_destination status=2"
I am currently rolling out a Postfix/Dovecot configuration on our servers to replace our monolithic mail server.
On the test enviroment I have everything set up and it worked there. Now I am rolling ...
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Is it possible to configure Postfix to receive emails on any email address on a domain name I control?
The question is mainly stated on the title. I was wondering if it is possible to configure Postfix in such way. More specifically, if I control domain "example.com" I'm asking if I will be ...
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How can I force PHP to go through my local Postfix SMTP instead of going straight to the destination?
I have a website with forms where users can send us requests. In addition, the site sends a predefined email to the client. The form receives spam (big surprise) and I'm trying to block emails from ...
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Is there a DNS-based policy like SPF or DMARC to require STARTTLS sessions for a given domain?
Ignoring the fact that not all mail servers support TLS:
Is there a way to announce to the world that we would prefer that our inbound mail be delivered via TLS and verified as signed by a trusted CA?
...
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Malformed hostname in an MX record, possible?
I'm wondering if it's possible to publish (and receive) a malformed hostname (e.g. a hostname starting with a digit or with a hyphen, etc.) in MX lookups? Does the DNS server usually validate MX ...
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sendmail: does `TLS_Clt` support CIDR-formatted network blocks in /etc/mail/access?
Does sendmail support TLS_Clt access matching based on blocks of IPs? So far the official sendmail TLS documentation I have found does not indicate that it does (nor that it doesn't).
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Can Postfix require TLS per-domain for inbound _and_ outbound addresses (or IPs)?
I want to reject email from certain senders (ie, the MAIL FROM sender) whose domain appears in a type:table map if the transport is not via STARTTLS. So if [email protected] sends an email then I ...
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Oracle Linux postfix conf SMTP - Default sender 'from' issue
How do I specify a default sender 'from:' address in postfix config for emails through smtp?
I'm trying to send emails through SMTP and a relay from two different servers with Oracle Linux 8
The ...
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Cannot properly send email in MacOS via postfix
Telling story short.
My MacOS version is: 12.4.
In /etc/postfix/:
In sasl_passwd i have:
smtp.emailsrvr.com:587 <myEmail>:<password>
In main.cf i have:
# custom POSTFIX email sender ...
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Python Scrips on Raspberry - ssh works, cronjob doesn't
I wrote a python script that checks a website and eventually sends an email. I copied the script to my raspberry and when I execute it via ssh it works fine. But when I let it execute by the crontab ...
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Telnet error - "Connection timed out"
I am trying to telnet a port at a client's location.
telnet someexampledomain.com 25
It shows:
Trying someexampledomain.com...
telnet: connect to address someexampledomain.com: Connection timed out
...
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How can I make GNU mailutils to use an external SMTP server?
Does anybody on this planet know what the equivalent GNU mailutils command to the following looks like?
Is this even possible without a local MTA with mailutils?
Using s-nail it works as intended.
s-...
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Send-only SMTP mail via postfix rejected by relayhost (550-Please turn on SMTP Authentication)
I want to configure a Centos 8 machine to send emails via an external SMTP relay. (I control the Centos box and have no control over the external relay).
I've read countless posts on how to set up ...
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Upgraded Postfix and now seeing "discarding EHLO keywords: CHUNKING" in maillog
Upgraded Postfix to 3.5.8-2.el8 on RHEL 8.5 and started seeing below in /var/log/maillog:
postfix/smtpd[7575]: discarding EHLO keywords: CHUNKING
Reviewed main.cf and master.cf but can't see any ...
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Postfix cant fix open relay
postfix configuration:
~ # postconf -n | grep mynetworks
mynetworks = 127.0.0.0/8
mynetworks_style = host
smtpd_recipient_restrictions = permit_mynetworks, permit_sasl_authenticated, reject
...
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clamsmtpd won't start with the user specified in clamsmtpd.conf
Since I upgraded my server from Debian Stretch to Debian Buster, clamsmtpd is always running under the clamsmtp user althoug I specified to run under the clamav user in /etc/clamsmtpd.conf file. Here ...
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Postfix error for office365: TLS library problem - wrong version number
I am trying to reconfigure a (currently working) debian 10 postfix configuration because we have moved to Office365 as SMTP server. The postfix mail configuration is only used for sending out mails ...
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Can msmtp rewrite *all* recipient addresses?
I'm using msmtp to deliver system email from an Ubuntu server via an SMTP account.
Can I somehow configure this setup to rewrite all emails to one specific recipient address? If so, how?
Or put ...
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mutt error sending mail: gnutls_handshake: An unexpected TLS packet was received
I keep on getting an error as indicated by the title sending email in neomutt, This is what I put in my muttrc:
set from = "[email protected]"
set realname = "my name"
set ...
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3
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Postfix: sending outgoing mail through port 465/587 locally
I've got a mail server set up using postfix, dovecot, opendkim, and spamassassin. After a bit of hassle, I managed to get incoming mail working--I even set this account up using that server.
However, ...
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How can I identify what process is sending emails?
My email service provider has informed me that I keep hitting my daily SMTP quota limit and has identified one of my servers as sending email from a root account.
I've disabled any cronjobs that were ...
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Postfix: "Relay access denied"
I've been trying to set up a mail server, with dovecot, postfix, opendkim, and spamassassin. After some hassle I managed to get incoming mail working (I signed up for this account with the email!). ...
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Relay access denied only for one machine?
So i have a postfix relay that works for my first machine (SLE12 SP5) but not for my second one (SLE12 SP4).
Both machines are in the same domain, they are also in the same local network and same ...
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connection to blacklisted host DNSBL
I’m trying to build a mail server, but when I tried to check the if TCP Port 25 (outbound) is blocked or not
I got the following
root@mail:~# telnet gmail-smtp-in.l.google .com 25
Trying 74.125.71.27…
...
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