> morning, and expected all to be well. Soon after the reload, we began to see
> our SMTP service go painfully slow, only allowing a trickle of emails to get
> in. So the rcpthosts list going blank and then being rebuilt is not the
Well, it may not be a real problem, it may be just slow connections
using up your concurrency. In this case it should eventually sort
itself out.
Having said that, you don't mention whether the box is very busy nor
what sort of internet connection you have. That would be useful to
know. Futhermore, you don't say whether SMTP deliveries are occuring
or not. Is the qmail-send log ticking over with new deliveries?
While Matt might have omitted some useful information, he does however
make our life a lot easier because he gives plain data and the *real*
domain. This allowed me to do a couple of test connections to his
server which makes things a lot clearer. Here's what happens for me:
$ telnet mail1.godaddy.com 25
Trying 63.241.136.35...
telnet: connect to address 63.241.136.35: Network dropped connection on reset
telnet: Unable to connect to remote host
Thanks Matt. That tells me a lot. Specifically that the port is being
listened to - so tcpserver is running correctly, that connections are
being accept - so the tcpserver listen socket hasn't reach the backlog
limit, but then something fails...
> I have noticed that if I do a "qmail stop" and then a "qmail start", about
> 20 successful SMTP connections immediately come in, and then even though
This is a worry as your tcpserver line has a concurrency of 120 as
shown here.
> Here is the tcpserver line I am currently using for smtp:
>
> 22482 ? S 0:00 /usr/local/bin/tcpserver -v -l
> mail1.godaddy.com -P -H -R -x /etc/tcp.smtp.cdb -c 120 -u 503 -g 502 0 smtp
> /var/qmail/bin/qmail-smtpd
I'd expect you to see a lot more than 20 qmail-smtpd processes
running.
In conjunction with the results of the telnet test I suspect a limits
problem that is stopping tcpserver from forking as many processes as
it wants.
Do you log the tcpserver output? If so, what does it show? If not, can
you start logging (I don't know whether LWQ includes this).
Does your tcpserver start script use softlimit to set the process
limits? If so, can you include -p130 or some such? However tcpserver
is started you'll need to raise the limit on the number of children it
can fork.
Regards.
