Putting all outgoing mail on hold?

Jesper Dybdal

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Mar 17, 2012, 10:48:32 AM3/17/12

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Is there a simple way to put all outgoing mail (i.e., everything that
would normally be processed by the default "smtp" instance) into the
HOLD queue?

The reason I would like to do that is that the IP address on which I run
my little server is about to change, and I would like outgoing mail to
be held until I am sure that the new address has a proper reverse DNS
and is not in any problematic DNSBLs. I could also just block outgoing
port 25 with a firewall rule, but using HOLD will give me better
control: I can then release individual mails if I want to.
--
Jesper Dybdal, Denmark.
http://www.dybdal.dk (in Danish).

Noel Jones

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Mar 17, 2012, 7:12:36 PM3/17/12

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On 3/17/2012 9:48 AM, Jesper Dybdal wrote:
> Is there a simple way to put all outgoing mail (i.e., everything that
> would normally be processed by the default "smtp" instance) into the
> HOLD queue?
>
> The reason I would like to do that is that the IP address on which I run
> my little server is about to change, and I would like outgoing mail to
> be held until I am sure that the new address has a proper reverse DNS
> and is not in any problematic DNSBLs. I could also just block outgoing
> port 25 with a firewall rule, but using HOLD will give me better
> control: I can then release individual mails if I want to.

You can use a check_recipient_access map that puts everything
non-local on hold.

This needs to be the first rule in one of the smtpd_*_restrictions
sections so that all SMTP mail will be subjected to it. And, as a
guideline, you don't want rules of this sort in
smtpd_recipient_restrictions due to the danger of a typo mistake
making you an open relay.

Note that smtpd restrictions don't apply to mail submitted via the
sendmail(1) command line interface -- such as users with a login
shell, system/cron mail, sometimes webmail.

It would probably be prudent to do the firewall block until you see
where mail is going.

Also note that HOLD is a message-level restriction. If a message
has both local and non-local recipients, all will be put on HOLD.

# main.cf
smtpd_sender_restrictions =
check_recipient_access =
regexp:/etc/postfix/hold_outgoing.regexp

# hold_outgoing.regexp
/example\.com$/ DUNNO skip my domain
/^/ HOLD outgoing delivery suspended

-- Noel Jones

Wietse Venema

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Mar 17, 2012, 7:42:41 PM3/17/12

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Jesper Dybdal:

> Is there a simple way to put all outgoing mail (i.e., everything that
> would normally be processed by the default "smtp" instance) into the
> HOLD queue?

# postconf -e 'default_transport = retry:waiting for remote server upgrade'

Wietse

Vishal Agarwal

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Mar 18, 2012, 12:41:10 AM3/18/12

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Hi,

I have read somewhere that if you put "/^Received:/ HOLD" in header
checks; then all the message will be in queue and will be waiting for
delivery. In such case after getting all the message hold, you can use
postsuper -H [-H queue_id (un-hold)] to deliver selected messages.

Thanks/regards,
Vishal Agarwal

-----Original Message-----
From: owner-pos...@postfix.org
[mailto:owner-pos...@postfix.org] On Behalf Of Noel Jones
Sent: Sunday, March 18, 2012 5:13 AM
To: postfi...@postfix.org
Subject: Re: Putting all outgoing mail on hold?

On 3/17/2012 9:48 AM, Jesper Dybdal wrote:

> Is there a simple way to put all outgoing mail (i.e., everything that
> would normally be processed by the default "smtp" instance) into the
> HOLD queue?
>

Jesper Dybdal

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Mar 18, 2012, 6:45:19 AM3/18/12

to

I wrote:

>Is there a simple way to put all outgoing mail (i.e., everything that
>would normally be processed by the default "smtp" instance) into the
>HOLD queue?

Thanks for the responses.

Considering the disadvantages of using the HOLD state that Noel
describes, I think I'll use Wietse's suggestion. Though it doesn't
allow releasing individual messages, it is at least a much cleaner way
to do it than blocking with a firewall rule.