conversation timed out while sending RCPT TO

Arthur Titeica

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Apr 21, 2011, 9:38:41 AM4/21/11

to

Hello.

I am having some problems sending mail to one of the Bluehost servers (box467.bluehost.com 74.220.219.67)

Postfix logs that the conversation timed out while sending RCPT TO and indeed it takes some time until the server
sends an OK after the RCPT TO (in a telnet session).

The question on the Postfix side is: can I increase somehow this timeout period? And for best results I would really
like this to happen specifically for this server.

Further details follow as maybe somebody has some previous experience with such abusive behavior from Bluehost.

The telenet session goes as

============================
$ telnet example.com 25
Trying 74.220.219.67...
Connected to example.com.
Escape character is '^]'.
220-box467.bluehost.com ESMTP Exim 4.69 #1 Thu, 21 Apr 2011 03:20:15 -0600
220-We do not authorize the use of this system to transport unsolicited,
220 and/or bulk e-mail.
EHLO psw.ro
250-box467.bluehost.com Hello psw.ro [94.62.132.84]
250-SIZE 52428800
250-PIPELINING
250-AUTH PLAIN LOGIN
250-STARTTLS
250 HELP
MAIL FROM: <>
250 OK
RCPT TO: off...@example.com
250 Accepted
DATA
354 Enter message, ending with "." on a line by itself
test
.
550 Administrative prohibition
QUIT
221 box467.bluehost.com closing connection
============================

Notice that it rejects with "550 Administrative prohibition" which is yet something I will have to deal with once I
get over the RCPT TO timeout.

The bottom line is that sending from Gmail works which indicates some blacklisting on their side.

--
Arthur Titeica
PharmEc Software

Wietse Venema

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Apr 21, 2011, 10:03:26 AM4/21/11

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Arthur Titeica:

> Hello.
>
> I am having some problems sending mail to one of the Bluehost servers (box467.bluehost.com 74.220.219.67)
>
> Postfix logs that the conversation timed out while sending RCPT
> TO and indeed it takes some time until the server
> sends an OK after the RCPT TO (in a telnet session).
>
> The question on the Postfix side is: can I increase somehow this
> timeout period?

Increase smtp_rcpt_timeout (default: 300s).

> And for best results I would really like this to happen specifically
> for this server.

You may want to use a transport map for this.

/etc/postfix/master.cf
slow_rcpt unix - - n - - smtp
-o smtp_rcpt_timeout=1000s

/etc/postfix/main.cf:
transport_maps = hash:/etc/postfix/transport

/etc/postfix/transport:
# Specify the recipient's domain name, not the MTA hostname.
bluehost.com slow_rcpt:

Commands:

# postmap hash:/etc/postfix/transport
# postfix reload

Documentation:

http://www.postfix.org/postconf.5.html#smtp_rcpt_timeout
http://www.postfix.org/transport.5.html
http://www.postfix.org/master.5.html

Wietse

Arthur Titeica

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Apr 21, 2011, 10:16:34 AM4/21/11

to

On Thursday 21 April 2011 17:03:26 Wietse Venema wrote:
> Arthur Titeica:
> > Hello.
> >
> > I am having some problems sending mail to one of the Bluehost servers
> > (box467.bluehost.com 74.220.219.67)
> >
> > Postfix logs that the conversation timed out while sending RCPT
> > TO and indeed it takes some time until the server
> > sends an OK after the RCPT TO (in a telnet session).
> >
> > The question on the Postfix side is: can I increase somehow this
> > timeout period?
>
> Increase smtp_rcpt_timeout (default: 300s).

Thanks for this. I couldn't find it on my own ;).

Since the timeout is quite big by default I can't imagine it will solve
anything if I increase it but I'll give a try.

>
> > And for best results I would really like this to happen specifically
> > for this server.
>
> You may want to use a transport map for this.
>
> /etc/postfix/master.cf
> slow_rcpt unix - - n - - smtp
> -o smtp_rcpt_timeout=1000s
>
> /etc/postfix/main.cf:
> transport_maps = hash:/etc/postfix/transport
>
> /etc/postfix/transport:
> # Specify the recipient's domain name, not the MTA hostname.
> bluehost.com slow_rcpt:
>
> Commands:
>
> # postmap hash:/etc/postfix/transport
> # postfix reload
>
> Documentation:
>
> http://www.postfix.org/postconf.5.html#smtp_rcpt_timeout
> http://www.postfix.org/transport.5.html
> http://www.postfix.org/master.5.html
>
> Wietse

--
Arthur Titeica
PharmEc Software

Wietse Venema

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Apr 21, 2011, 10:40:43 AM4/21/11

to

Arthur Titeica:
[ Charset ISO-8859-1 unsupported, converting... ]

> On Thursday 21 April 2011 17:03:26 Wietse Venema wrote:
> > Arthur Titeica:
> > > Hello.
> > >
> > > I am having some problems sending mail to one of the Bluehost servers
> > > (box467.bluehost.com 74.220.219.67)
> > >
> > > Postfix logs that the conversation timed out while sending RCPT
> > > TO and indeed it takes some time until the server
> > > sends an OK after the RCPT TO (in a telnet session).
> > >
> > > The question on the Postfix side is: can I increase somehow this
> > > timeout period?
> >
> > Increase smtp_rcpt_timeout (default: 300s).
>
> Thanks for this. I couldn't find it on my own ;).

To see all timeout parameters:

$ postconf | grep timeout

> Since the timeout is quite big by default I can't imagine it will solve
> anything if I increase it but I'll give a try.

Another possibility is that the receiver has a broken implementation
of SMTP command pipelining.

Here, Postfix sends "MAIL FROM", "RCPT TO" and "DATA" commands
together, and some busted firewalls will screw it up.

To try that possibility

/etc/postfix/master.cf
really_busted unix - - n - - smtp
-o smtp_rcpt_timeout=1000s
-o smtp_discard_ehlo_keywords=pipelining

/etc/postfix/main.cf:
transport_maps = hash:/etc/postfix/transport

/etc/postfix/transport:
# Specify the recipient's domain name, not the MTA hostname.

bluehost.com really_busted:

Arthur Titeica

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Apr 21, 2011, 4:46:36 PM4/21/11

to

I'm speechless.

postfix/smtp[1311]: 1222F440344: to=<off...@example.com>, relay=example.com[74.220.219.67]:25,
delay=13, delays=0.05/0.01/1.5/12, dsn=2.0.0, status=sent (250 OK id=1QD0Vp-0005U8-IE)

After 2 days listening non-sense at Bluehost support your clear and concise help proves once again invaluable.

I don't post much on this list but I read it when I get the time. Let me take the opportunity to say that I really
admire your work. I have yet to find another project (free, paid or whatever) that offers the same level of quality in
execution, documentation and support.

>
> /etc/postfix/main.cf:
> transport_maps = hash:/etc/postfix/transport
>
> /etc/postfix/transport:
> # Specify the recipient's domain name, not the MTA hostname.
> bluehost.com really_busted:
>
> Commands:
>
> # postmap hash:/etc/postfix/transport
> # postfix reload
>
> Documentation:
>
> http://www.postfix.org/postconf.5.html#smtp_rcpt_timeout
> http://www.postfix.org/transport.5.html
> http://www.postfix.org/master.5.html
>
> Wietse

--
Arthur Titeica
PharmEc Software