Re: sending/receiving email is VEEEEEERY slow

Customer Support Server/Network Issues
1

I’m reactivating this very old topic, 'cause I’m having the same problem as stated in the first posts in this thread.

SMTP Sessions to mail.domain.com are almost timing out in mail apps, and when doing a telnet to port 25 it takes 30-50 seconds until the welcome message appears.

I’ve done some investigation and found out that from some IP’s the smtp sessions are doing well, and from others this timeout occurs. The only difference that I found out between these IP’s (belonging, of course, to different providers) that those that the IP’s that give timeout have an incorrect (incorrect, NOT inexistent!) reverse DNS entry.

The problem is that only these smtp servers, hosted by Jodo, are giving this delayed connection when sending mail from those “incorrect” IP’s. Connecting to other mail servers (I’ve tried several random chosen servers from Free SMTP Server List - SMTP Servers - 2026 ) gives no delay or timeout when starting the telnet session.

Is there anyting you can do to your mail server configuration?

LE: I gaved no personal data (actual domain, etc) 'cause I didn’t know if it isn’t beak the policy of the forum.

2

Hi Cosinus,

I understand what you are saying. This is default behavior of our mail systems. Having an IP with no rDNS is a very bad sign.
Really, any mail server on the internet sending email MUST have an rDNS. Any good ISP should have the same

3

Hello, Yash.

Thank you for your response.

The problem is not an IP with NO reverse DNS, is an IP with MISCONFIGURED (I think) IP.

Let me be more specific. When initiating the SMTP connection on port 25 it takes a lot of time until the welcome message (220 mailx.m****here.biz ESMTP) from your mail servers arrives. After that the “conversation” is smooth.

This delay also does not appear when using an IP with NO reverse DNS.

This delay also does NOT appear when connecting to any of other SMTP servers (well, I tried only about 30 from the list in the above given URL), only when connecting to Jodo’s mail servers.

Is there a chance that something is misconfigured in your mail servers? Something that your sysadmins have overseen, someting that doesn’t appear very often, given the fact that those ‘strange’ IP’s are not very common?

LE: I see now that the thread inherited the subject from the splitted topic. “Receiving” mail is not slow, POP session are not affected.

4

Nobody to talk to me about this issue?

5

REALLY nobody?? :frowning:

6

What server your mailapps are hosted on?

7

MX record: mail5.jodoshared.com / mail2.jodoshared.com

That’s for now. I’ve signed up for a Value Windows trial account (which is expiring tomorrow, Thursday - that’s why the hurry for a response), having in mind to apply for a reseller account - so the mail servers will most probably change.

8

Ok, tanmaya, I know that you are a very busy person, but I would like to have my problem solved.

I know such a problem is difficult to investigate, so, if you want, we can meet in an online chat (Livechat support, YM or whatever) and to try to solve it, me to do the tests and you to investigate on your side.

To have a start for this investigation, here are two logs. A SMTP connection for sending an email. The first session has set the timeout period at 30 seconds:

Thu 2006-11-23 18:43:32: [-1:13] > From: [email protected]
Thu 2006-11-23 18:43:32: [-1:13] > To: [email protected]
Thu 2006-11-23 18:43:32: [-1:13] > Subject: test
Thu 2006-11-23 18:43:32: [-1:13] > Message-ID: [email protected]
Thu 2006-11-23 18:43:32: [-1:13] Attempting to send message to gateway.
Thu 2006-11-23 18:43:32: [-1:13] Attempting SMTP connection to [mail5.mydomain.com : 25]
Thu 2006-11-23 18:43:32: [-1:13] A-record resolution of [mail5.mydomain.com] in progress (DNS Server: 194.102.204.101)…
Thu 2006-11-23 18:43:32: [-1:13] D=mail5.mydomain.com TTL=(362) A=[64.187.103.252]
Thu 2006-11-23 18:43:32: [-1:13] Attempting SMTP connection to [64.187.103.252 : 25]
Thu 2006-11-23 18:43:32: [512:13] Waiting for socket connection…
Thu 2006-11-23 18:43:33: [512:13] Socket connection established
Thu 2006-11-23 [COLOR=“Red”]18:43:33: [512:13] Waiting for protocol initiation…
Thu 2006-11-23 [COLOR=“Red”]18:44:03: [512:13] 30 second wait for protocol timeout exceeded.
Thu 2006-11-23 18:44:03: [512:13] SMTP session abnormally terminated, 0 bytes transferred.
Thu 2006-11-23 18:44:03: ----------

For the second session, I’ve raised the timeout period to 60 seconds:

Thu 2006-11-23 18:44:37: [-1:15] > From: [email protected]
Thu 2006-11-23 18:44:37: [-1:15] > To: [email protected]
Thu 2006-11-23 18:44:37: [-1:15] > Subject: test
Thu 2006-11-23 18:44:37: [-1:15] > Message-ID: [email protected]
Thu 2006-11-23 18:44:37: [-1:15] Attempting to send message to gateway.
Thu 2006-11-23 18:44:37: [-1:15] Attempting SMTP connection to [mail5.mydomain.com : 25]
Thu 2006-11-23 18:44:37: [-1:15] A-record resolution of [mail5.mydomain.com] in progress (DNS Server: 194.102.204.101)…
Thu 2006-11-23 18:44:57: [-1:15] D=mail5.mydomain.com TTL=(360) A=[64.187.103.252]
Thu 2006-11-23 18:44:57: [-1:15] Attempting SMTP connection to [64.187.103.252 : 25]
Thu 2006-11-23 18:44:57: [532:15] Waiting for socket connection…
Thu 2006-11-23 18:45:02: [532:15] Socket connection established
Thu 2006-11-23 [COLOR=“Red”]18:45:02: [532:15] Waiting for protocol initiation…
Thu 2006-11-23 [COLOR=“Red”]18:45:38: [532:15] 220 mail5.mhere.biz ESMTP
Thu 2006-11-23 18:45:38: [532:15] EHLO mydomain.com
Thu 2006-11-23 18:45:38: [532:15] 250-mail5.mhere.biz
Thu 2006-11-23 18:45:38: [532:15] 250-PIPELINING
Thu 2006-11-23 18:45:38: [532:15] 250-8BITMIME
Thu 2006-11-23 18:45:38: [532:15] 250-SIZE 52428800
Thu 2006-11-23 18:45:38: [532:15] 250 AUTH LOGIN PLAIN CRAM-MD5
Thu 2006-11-23 18:45:38: [532:15] MAIL From:[email protected] SIZE=646
Thu 2006-11-23 18:45:39: [532:15] 250 ok
Thu 2006-11-23 18:45:39: [532:15] RCPT To:[email protected]
Thu 2006-11-23 18:45:39: [532:15] 250 ok
Thu 2006-11-23 18:45:39: [532:15] DATA
Thu 2006-11-23 18:45:39: [532:15] 354 go ahead
Thu 2006-11-23 18:45:39: [532:15] Sending <C:\MDAEMON\REMOTEQ\pd50000000001.msg> to [64.187.103.252]
Thu 2006-11-23 18:45:39: [532:15] Transfer Complete.
Thu 2006-11-23 18:45:39: [532:15] 250 ok 1164300105 qp 19526
Thu 2006-11-23 18:45:39: [532:15] QUIT
Thu 2006-11-23 18:45:40: [532:15] 221 mail5.m****here.biz
Thu 2006-11-23 18:45:40: [532:15] SMTP session successful, 704 bytes transferred.
Thu 2006-11-23 18:45:40: ----------

As you see, the “protocol initiation” takes over 30 seconds, sometimes 40 or 50, and that is the problem. And it occurs only when sending emails from IP addresses that have wrong reverse DNS entries AND only to servers hosted by me trough you.

This log was created with MDaemon, I’ve installed it to have a timestamped log. But for everyday use, my customers use e-mail clients like Thinderbird, and setting another timeout period is if not difficult but for sure annoying - why to wait 30 - 50 seconds for an email to be sent?

Please be kind and help me in this issue, because I’m running out of excuses for my customers…

9

Please try this “SSL enabled” port 465. Let me know if this works fine for you or no.

10

No, it does not help, it still times out.

11

Are you using SSL as said?

12

Yes! You said SSL, I switched Authenitcation to SSL, on port 465 (default)!

13

I’ve tested it now, and now it has been worked out ok (note that I did not changed the settings in the e-mail client since last night, and then it was not working).

Now it remains the certificate issue: every time I try to send an email a warning show up regarding the SSL certificate (Security error: domain name mismatch / Connection with mail.mydomain.com, certificate belonging to .m***here.biz, etc). This warning, again, would be annoying for my cusotmers.

14

No changes done by me either since i asked you about SSL.
Your clients can use mailx.m****here.biz (where x is the mailserver number) to avoid this warning. This is due to nature of SSL that it can have just one hostname.

15

So that’s the point where we meet halfway: I can’t ask the big, ugly and unfriendly provider to solve his rDNS problems, and so I have to use another SMTP server.

But, still, why is the long time period when connecting to the SMTP server?

16

It is rDNS. It is integral part of some functionality/filtering used in our mailservers.