New answers tagged smtp
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Sendmail unable to find recipient to send email
When stuff foes wrong on your server the FIRST PLACE TO LOOK IS IN YOUR LOGS.
reason: 550 5.1.1 [email protected]... User unknown
There are 2 possible scenarios here (which one applies is ...
- 21.9k
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Is opening SMTP port with default Sendmail config safe?
Outgoing SMTP is not a problem. Incoming could be.
Make sure in your sendmail config that you are not an open relay.
You could run this to prevent an open relay
sudo sh -c 'echo "FEATURE(`...
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Accepted
Is opening SMTP port with default Sendmail config safe?
Yes, you're very probably running a wide-open mail server and will shortly become a spam source if you aren't one already. You do not need to be able to receive email in order to send it. In your ...
- 1,406
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Accepted
Default SMTP functionality if one of multiple addresses is invalid
When you have one email with multiple receivers where one is invalid, the mail server tries to send the email until it encounters the email address with the error. Then it usually sends a non-delivery ...
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Can I generate and log output alerts for SMTP traffic using Suricata 7.0.2?
Suricata already contains smtp rules by default
https://github.com/OISF/suricata/blob/master/rules/smtp-events.rules
But if you enable more sources and fetch/update those rules you get more smtp rules....
- 1,453
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What exactly is Return-Path and who sets it?
The Return-Path email header is supposed to contain the last known bounce address from the latest SMTP handshake in delivery path. Unlike e.g. Received headers, the existing Return-Path headers in the ...
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