Topic: [DDCLIENT] MailHop from Dyndns delaying for 8 hours

[soprom]

I'm using a mail relay service in order to bypass port 25 blocked by ISP.
This mail hop has recently caused an 8 hours delay before emails reached my server.

Dyndns web site says this (FAQ) :

Why is my mail through the MailHop service being delayed, sometimes as long as a day or two, even when my server is up?

The most likely explanation for this type of delay is that your mail server is performing what is known as "tarpitting". When your server is receiving a message that it is configured to not receive, rather than rejecting it as the standard SMTP procedure would be, it is simply holding open the connection, without sending any data, until it times out. If you are using any of our MailHop services, you MUST disable this type of functionality. Tarpitting will only cause serious problems for our mail server, and will cause delivery of legitimate mail to be delayed, because our server will think your server is broken, and will wait longer between delivery attempts. In some cases, this mis-configuration of your mail server can even cause legitimate messages to time out before they are delivered. If you want to implement content filters on your mail server, you MUST reject messages with an SMTP 5xx error code. Any other behavior will cause serious problems.

Can I conclude that disabling antispam on my server would be a solution?
(SME7.1)

[CharlieBrady]

I
Can I conclude that disabling antispam on my server would be a solution?

No.

[soprom]

Thanks Charlie!

Should I suspect Dyndns overload instead of worrying about my server?

[CharlieBrady]

Should I suspect Dyndns overload instead of worrying about my server?

That's certainly possible. You shouldn't conclude anything without evidence.

[william_syd]

I'm using a mail relay service in order to bypass port 25 blocked by ISP.
This mail hop has recently caused an 8 hours delay before emails reached my server.

All mails get delayed ?

I use mailhop with 7.0 now 7.1 and all is fine. Test emails from gmail come in at under 30 seconds of sending.

Your mail arrives from 4 or 5 mailhop servers only so greylisting and SPF will not work effectively.

[soprom]

As Charlie mentionned, evidences were needed...
A sample mail header shows this:

Received:
from mxout3.mailhop.org
   by <my server> (qpsmtpd/0.32) with ESMTP;
   Thu, 22 Feb 2007 20:58:39 -0500

Received:
from mxin2.mailhop.org
   by mxout3.mailhop.org with esmtp (Exim 4.63)
   Thu, 22 Feb 2007 13:48:35 -0500

Received:
from tomts8-srv.bellnexxia.net
   by mxin2.mailhop.org with esmtp (Exim 4.63)
   Thu, 22 Feb 2007 13:48:30 -0500

Received:
from toip12-bus.srvr.bell.ca
   by tomts8-srv.bellnexxia.net
   Thu, 22 Feb 2007 13:48:30 -0500

Received:
from relais.videotron.ca  
   by toip12-bus.srvr.bell.ca with ESMTP;
   22 Feb 2007 13:48:29 -0500

It shows a long delay between mxout3.mailhop.org and my server.
Many (20+) mails arrived together after the same delay. It does not seem to be frequent but it happends on a bad day (users were expecting those mails "now").

mxout3.mailhop.org just sent a bunch of emails in one shot.

I think it is not relevent to this forum and I should ask dyndns.

[soprom]

Dyndns says:

I checked our logs and it looks like your server was timing out for
quite sometime, which is why your messages were delayed. Our server
kept retrying the entire period your server was inaccessible, and it
was able to send you mail successfully at 20:58:32.

This might be a problem with ddclient. I see in messages that ddclient was updated at:

Feb 22 20:18:07 serveur ddclient: /etc/ppp/ddclient_ip-up.local ppp1 /dev/pts/1 460800 192.168.99.5 192.168.99.144 pptpd
F

This the time when all mails were received. I have an other server with the same ISP having a problem to sync IP address.

The problem is now targetting ddclient contribs.

How do I transfer a thread to a different forum?