E-Mail-Notification Send Test-Mail results in E-Mail-Account-Lockdown

Hello!

Yesterday I tried to set up the E-Mail-Notification and alway got 501 errors and the failure "E-Mail-Sender-Adress from ISP not allowed" when I tried to send a Test-E-Mail.

It took a few tries to solve this problem, but finally I could solv the problem.

A short time later suddenly I can´t receive or send E-Mails anymore. My password was always rejected. I thought that my ISP had server problems, so I decided to wait until today morning. But today I still had the same problem. Finally I called the tech hotline of my ISP for helping me. They said, that my Account was disabled because I sent more than 500 mails the last 2 days.
I only sent a few Test-E-Mails manually yesterday and I don´t have any virus?

How can I encircle this failure to prevent happening this once again? The syslogs doesn´t give me a hint how many mails were sent yesterdy.

Zitat von BlueCoffee

Who are you with? I have gmx.com for stuff like this.

My local ISP: liwest

Zitat von votdev

If your system is in a bad shape monitd can flood your email queue. To prevent filling the email queue there is a daily cron job that kills all emails. So i'm wondering what is going on.

I shutdown my server after I configured the E-Mail-Notification successfully yesterday (I finally received the Test E-Mail). So the 500 E-Mails must have been sent within 1 hour during I was solving the problem. So the daily cron job couldn´t contain the problem, I think.

So I downloaded and checked the syslog yet and the log is filled with errors, although I only hit a few times the Test-Button:

Dec  6 21:14:42 s940 postfix/smtp[17769]: 106995A1: replace: header Subject: Undelivered Mail Returned to Sender: Subject: [S940.local] Undelivered Mail Returned to Sender

Dec  6 21:14:43 s940 postfix/smtp[17769]: 106995A1: to=<xxx@xxx.com>, relay=xx.xxx.at[212.33.55.20]:587, delay=14, delays=0/14/0.18/0.09, dsn=5.0.0, status=bounced (host xx.xxx.at[212.33.55.20] said: 501-Die Absenderadresse xxx@xxx.com darf nicht mit diesem 501-Mailkonto xxx verwendet werden. 501-The sender address (xxx@xxx.com) is not allowed for this 501 account. (in reply to end of DATA command))

Is there a way to limit the maximal outgoing amount of mails per day?

So far I could find out, postfix has no option to limit the maximum amout of outgoing mails.

Postfix Configuration Parameters

"Postfix does not have built in support for rate limiting, you will have to use a policy daemon for that. a good one is policyd:"

About

I also find that Guide: This document is geared towards using Policyd (cluebringer) on Ubuntu to limit mail with Postfix.

But unfortunalely this is for a beginne like me to complex.

There are some workarounds to embark the amount of outgoing mails per time unit:

Rate Limiting with Postfix

Postfix: limit outgoing mail throttling

Postfix : Rate limit based on recipients throttling

Example:

smtpd_client_message_rate_limit = 2
anvil_rate_time_unit = 60s

The above settings will allow a given user to send a maximum of two messages per minute. Note that the anvil_rate_time_unit setting is also used to control other timeouts. The postfix documentation mentioned that the default value is 60s—I basically only included it for conciseness.

default_destination_rate_delay = 5s

This puts a 5 second delay between each outbound smtp connnection to the same destination. There are other default_destination parameters that maybe of use to you on the man page......

NOTE:

The resulting behavior depends on the value of the corresponding
per-destination recipient limit.

The delay is enforced by the queue manager. The delayTtimer state does not survive "postfix reload" or "postfixstop".

Can I directly edit the file "main.cf.j2" and paste the options obove at the end of the file for testing, or will OMV overwrite my mods?

I installed yesterday "Fail2ban" and see that at the fileld "Dest email" ist the adress "root@localhost" inscribed.

Is it possible to send an E-Mail only within my LAN with postfix and receive it with thunderbird? That would be all I need for now.

I found this: How to setup a Linux LAN local mail? .. so it should be possible

For testing purpose I created a file called "11main_custom.sls" in the directory /srv/salt/omv/deploy/postfix:

customize_postfix_main:
  file.append:
    - name: "/etc/postfix/main.cf"
    - text: |
        smtpd_client_message_rate_limit = 1
        anvil_rate_time_unit = 10m
        default_destination_rate_delay = 10m
        default_destination_recipient_limit = 1

In terminal I tried to execute: sudo omv-salt deploy run postfix but I got an error:

raspberrypi:

Data failed to compile:

----------

Rendering SLS 'base:omv.deploy.postfix.11main_custom' failed: found a tab character where an indentation space is expected

[CRITICAL] Rendering SLS 'base:omv.deploy.postfix.11main_custom' failed: found a tab character where an indentation space is e xpected