Linux Tutorials on the topic “postfix”

  • On sending emails, I get the following error message: "Relaying denied".

    apache Author: tillTags: , Comments: 0

    There are two solutions for this problem: 1) You configure your MTA to allow authentication via SMTP (SMTP-Auth). Your users then have to change settings in their email clients (e.g. Outlook), i.e., they have to activate Server requires authentication. 2) You install "POP-before-SMTP" or poprelayd on your server. Your users then have to fetch emails first before they are allowed to send emails for a restricted period of time (mostly 30 min.).

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  • How do I configure Postfix to use SMTP-Auth?

    apache Author: tillTags: Comments: 0

    Some useful links: http://www.thecabal.org/~devin/postfix/smtp-auth.txt http://www.mandrakesecure.net/en/docs/postfix-sasl.php http://postfix.state-of-mind.de/patrick.koetter/smtpauth/index.html http://www.howtoforge.com/perfect_setup_debian_sarge http://www.howtoforge.com/howto_postfix_smtp_auth_tls_howto

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  • I cannot send and/or receive emails.

    apache Author: tillTags: , , Comments: 0

    Please check if Sendmail/Postfix and your POP3 daemon are running by executing netstat -tap You will get a list of all services listening on your server. If they are running re-configure your firewall (iptables or ipchains) so that the ports 25 (Sendmail/Postfix) and 110 (POP3) are not blocked. If this does not help please check that Sendmail/Postfix is really running on port 25 and your POP3 daemon on port 110. (Hint for standard RedHat installations: If you have webmin installed and are running Sendmail, go to Webmin->Servers->Sendmail->Sendmail Options. Under SMTP Port Options you often find the following entry:

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  • One of the users on the system has a CatchAll-email address. He receives all emails, even those for users of another site...

    apache Author: tillTags: , Comments: 0

    One of the users on the system has a CatchAll-email address. He receives all emails, even those intended for users of another site on the same server. The MTA on the server is postfix. Please check if the domain of the users that receives all emails is the same as the domain $mydomain in /etc/postfix/main.cf. If this is the case, change $mydomain and run postfix reload on the shell. You should never enter a domain that is used for a virtual site on the server as $mydomain in /etc/postfix/main.cf!

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  • Postfix-SMTP-AUTH-TLS-Howto

    Author: falkoTags: Comments: 1

    Postfix-SMTP-AUTH-TLS-Howto This document describes how to install a mail server based on postfix that is capable of SMTP-AUTH and TLS. It should work (maybe with slight changes concerning paths etc.) on all *nix operating systems. I tested it on Debian Woody and Fedora Core 1 so far.

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  • Virtual Hosting with Postfix, part one

    Author: joeTags: Comments: 9

    Version 1.0 Author: Joe Topjian <joe [at] adminspotting [dot] net> Last edited 04/11/2005 The virtual domain support in Postfix is actually quite robust. There are three different ways you host virtual domains with Postfix and they're all described here. We'll be looking at the third one: separate domains and non-unix accounts. Why this one? Because in the end, this options gives us the most flexibility. It's a little more complicated to set up and understand but well worth it when you're hosting several domains.

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  • Virtual Hosting with Postfix, part two

    Author: joeTags: Comments: 3

    Version 1.0 Author: Joe Topjian <joe [at] adminspotting [dot] net> Last edited 04/15/2005 This article will pick up where the last one left off: how to actually retrieve the email we're storing in our virtual accounts. In the first article, I explained how we're using the third type of Postfix virtual hosting which is to use separate domains and non-unix accounts. The separate domains portion was covered fairly well. Now it's time to work on the non-unix accounts.

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  • Greylisting - fight Spam with Postgrey and Postfix on Debian and Ubuntu

    debian Author: erkTags: , , Comments: 9

    There are numerous ways to prevent spam from reaching your inbox, the most popular is probably SpamAssassin. Greylisting will not replace spam filtering software like SA but it will serve as a powerful first hurdle for spam thus reducing the ammount of spam entering the system at all.

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