Disabling inbound email in a jail

[Janos Dohanics]

On Friday 27 February 2009 10:49:22 am Kirk Strauser wrote:
> I only want sendmail in a jail to do one thing: forward nightly reports
> from root at localhost to a real account on another machine.  What's the
> proper way to configure this?  By default, sendmail_enable="NO" in
> /etc/rc.conf still gives a running sendmail that accepts mail from other
> hosts:
>
> me at realhost$ echo foo | mail me at jail.example.com
>
> me at jail.example.com$ tail -f /var/log/maillog
> Feb 27 09:43:37 jail.example.com sm-mta[86832]: n1RFhbBp086832:
> from=<me at realhost>, size=735, class=0, nrcpts=1,
> msgid=<20090227154335.877A442071 at realhost>, bodytype=7BIT, proto=ESMTP,
> daemon=Daemon0, relay=jail.example.com [10.0.5.70]
> Feb 27 09:43:37 jail.example.com sm-mta[86833]: n1RFhbBp086832:
> to=<me at jail.example.com>, delay=00:00:00, xdelay=00:00:00, mailer=local,
> pri=30983, relay=local, dsn=2.0.0, stat=Sent
>
> However, if I set sendmail_enable="NONE", then I can't send outbound email
> either:
>
> me at jail.example.com$ echo foo | mail me at realhost
> me at jail.example.com$ tail -f /var/log/maillog
> Feb 27 09:37:37 jail.example.com sendmail[86513]: n1RFbbg3086513: from=me,
> size=28, class=0, nrcpts=1,
> msgid=<200902271537.n1RFbbg3086513 at jail.example.com>, relay=me at localhost
> Feb 27 09:37:37 jail.example.com sendmail[86513]: n1RFbbg3086513:
> to=me at realhost, ctladdr=me (1001/1001), delay=00:00:00, xdelay=00:00:00,
> mailer=relay, pri=30028, relay=[127.0.0.1] [127.0.0.1], dsn=4.0.0,
> stat=Deferred: Connection refused by [127.0.0.1]
>
> What's the happy medium between "sendmail wide open" (eg
> sendmail_enable="NO" (WTF?)) and "disabled mail system" (eg
> sendmail_enable="NONE")?

You might want to disable sendmail and use mail/ssmtp - it's meant for 
scenarios just like yours.

-- 
Janos Dohanics