Viktor Dukhovni:
> > 09:22:43 mail4 postfix/smtpd[16278]: connect from unknown[137.99.149.148]
> > 09:22:45 mail4 postfix/smtpd[16278]: disconnect from unknown[137.99.149.148]
> >
> > 09:23:06 mail4 postfix/smtpd[16278]: connect from unknown[137.99.149.148]
> > 09:23:08 mail4 postfix/smtpd[16278]: disconnect from unknown[137.99.149.148]
> >
> > 09:23:12 mail4 postfix/smtpd[16278]: connect from unknown[137.99.149.148]
> > 09:23:15 mail4 postfix/smtpd[16278]: disconnect from unknown[137.99.149.148]
> >
> > 09:23:17 mail4 postfix/smtpd[16278]: connect from unknown[137.99.149.148]
> > 09:23:20 mail4 postfix/smtpd[16278]: disconnect from unknown[137.99.149.148]
>
> If the client is doing one delivery at a time with a new connection for each
> message, with no concurrency, what's interesting to see here is the spacing
> *between* connections, which is considerably longer than the duration of
> connections, which again hints at a possible DNS issue, but you have to
> look more closely.
The time from 'TCP connect' to the time that Postfix logs 'connect
from' includes the time to look up the client hostname (and if
available, IP address for that hostname). This -should- be quick,
but may be slow because of a problem in your local DNS.
Wietse
