Mail forward: 550 5.7.1 Anonymous client does not have permissions to send as this sender

emailpostfix

I want to install a small mailing list that forwards mails related to a specific project to all project members. So, let's say there are two members in that project userA@mailA.tld and userB@mailB.tld, and on my mail server server.tld I configured an alias by adding a line to my virtual maps:

project23@server.tld    userA@mailA.tld,userB@mailB.tld

So far, everything works as expected. If I send an email to project23@server.tld it gets forwarded to all users in that project. But it turns out that certain mail servers don't like to receive mails from foreign mail servers containing a From claiming to be sent from their domain. (Seems like especially Microsoft's SMTP servers have this problem). In that case I get a response like:

 [...] said: 550 5.7.1 Anonymous client does not have permissions to send as this sender. (in reply to RCPT TO command))

That means userA@mailA.tld is able to receive mails sent to project23@server.tld by userB@mailB.tld, but won't receive any mails sent from addresses in mailA.tld.

So my first question is: Did I isolate the problem correctly?

And if so, is there any smart workaround?

I could setup a real mailing list, so that mails are stored in an archive on the server and users get notifications/digests from a mail address like list@server.tld, but that would be too much overhead for our purposes…

Best Answer

Postfix: simple mailing list

Have you tried to create owner-project23@server.tld entry in virtual maps?

As I understand It should make postfix change envelope sender ("send bounces to") address of messages send to project23@server.tld and fix your problem.

http://www.postfix.org/VIRTUAL_README.html#mailing_lists

Using SSMTP:

You can find a detailed article here. (Please consider Zulakis' comment below regarding security: I let ssmtp solution here for your knowledge, but prefer postfix solution)

Install ssmtp

sudo aptitude install ssmtp

Edit the configuration file:

sudo vim /etc/ssmtp/ssmtp.conf

And configure it with your gmail account:

root=username@gmail.com
mailhub=smtp.gmail.com:587
hostname=username@gmail.com
UseSTARTTLS=YES
AuthUser=username
AuthPass=password
FromLineOverride=yes

Using Postfix

If you want to use your postfix install, you can configure it to work with your gmail account. You can find a detailed article here.

Check that you have all the needed dependencies

mailutils libsasl2-2 ca-certificates libsasl2-modules

Edit the configuration of postfix:

sudo vim /etc/postfix/main.cf

And configure it with your gmail account:

relayhost = [smtp.gmail.com]:587
smtp_sasl_auth_enable = yes
smtp_sasl_password_maps = hash:/etc/postfix/sasl_passwd
smtp_sasl_security_options = noanonymous
smtp_tls_CAfile = /etc/postfix/cacert.pem
smtp_use_tls = yes

Create the file with your password:

vim /etc/postfix/sasl_passwd

And add the following lines

[smtp.gmail.com]:587    USERNAME@gmail.com:PASSWORD

Allowing root only

I'm not exactly sure what you mean with

I don't want to allow other users/sites to send e-mail (like for example from PHP's mail())

But for blocking mail access per user or per domain, you can edit the following file:

vim /etc/mail/access

And add rules such as:

To:a1@server.vikas.com        REJECT            # Reject a1 user from recieving mails
From:a1@server.vikas.com     REJECT           # Reject a1 user from sending mails

I hope this helps.

Best Answer

Postfix: simple mailing list

Related Solutions

How to discard mails sent from a specific local user to external addresses

Postfix – How to Install for Sending Mails to Admin Only

Using SSMTP:

Using Postfix

Allowing root only

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