Re: Postfix smtpd DNS lookup delay

On Thu, 27 Sep 2007, in the Usenet newsgroup alt.os.linux.suse, in article
<785us4-9br.ln1@xxxxxxxxxxxxxxxxxxxxxxxx>, Bob Bob wrote:

One of course wonders whether this old guy is older than the other
old guy! <grin>

Old is a function of natural age (I'm over 0x41), mileage and rough
service. See the owners manual for recommended service intervals (not
that it matters, as you're probably long out of warranty anyway) ;-)

These sites are a private business that is only authoritive for the
private subnet (192.168 etc). They cant be connected to on the public
side at all. The DNS/postfix box is in fact only on a private subnet,
masquerading out for pop3 and smtp to the ISP as a relayhost.

If it's offering no services to the world, it's less of a risk, but
if it can connect out, there has to be a route "back in" to complete
the connection. Small risk, but still a risk.

Never thought of it either - the logging I was referring to is that
done by the mail server (if your system is using xinetd instead of
inetd, it may want to do logging based on the service configuration
file - look for the 'log_on_*' lines).

Err am not running an mail system under inetd. Its postfix.

Poorly worded on my part. Many servers want to (or can be configured
to) log the IP of remote systems that connect to them. An example of
this would be seen in [x]inetd. Stand-alone stuff - especially mail
servers - tend to have this logging on their own, as it's needed for
the 'Received:' header, never mind any logging that the administrator
may have required, or any hoops (example - connecting box must have
a PTR record, or must have matching PTR and A records, not be on any
blocklist, and must be in a country with an 'r' in the ISO3166 name
except on Tuesdays, when the magic letter is 's') that might be set
up as an anti-spam measure.

Old guy
.

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