Re: Why Postfix always complain "unexpected EOF" with my own tcp_table program?
- You can enable the debug mode of postfix smtp daemon (http://www.postfix.org/DEBUG_README.html). Then you can see the request and response which postfix talked with your tcp_table script.PS:From the postfix source code, it seems postfix has not received any response from your tcp_table. However postfix will retry 10 times for such scenario (sleep 1 sec before each retry).2013/7/28 Wietse Venema <wietse@...>
Zhang Huangbin:Caution: it is not a good idea to close a connection immediately> On Sunday, July 28, 2013 at 8:24 PM, Wietse Venema wrote:
> > 1) Use a network sniffer to see what Python actually sends. You may
> > assume that your program sends \n, but Postfix does not receive \n.
> Thanks Wietse, and John.
> I think this is the root cause, will try a network sniffer later.
> > 2) Unrelated to this bug: closing the connection after one request
> > is inefficient.
> My program closes the connection immediately.
after writing data to it. Some TCP/IP implementations may discard
unsent data when a connection is closed.
In Postfix, I avoid "write-close" bugs by keeping a connection open
until the receiver closes it (with of course a time limit that
forces the connection to be closed when things take too long).