On Tue, Nov 15, 2011 at 09:49:20PM +0200, Timo Sirainen wrote:
On Sat, 2011-11-12 at 05:32 +0100, Bambero wrote:
I configured dovecot to use submission smtp host becouse of chroot.
submission_host = 127.0.0.1
Unfortunatelly:
Nov 12 05:11:15 myhost exim[23366]: 2011-11-12 05:11:15 SMTP protocol synchronization error (next input sent too soon: pipelining was not advertised): rejected "EHLO myhost" H=localhost [127.0.0.1] next input="MAIL FROM:root@myhost\\r\\n"
This basically says that Dovecot's SMTP client is being noncompliant, because Exim doesn't advertise PIPELINING extension. But I'd rather not add more code to fix this, since PIPELINING gives you a little bit better performance anyway and you can most likely fix this by modifying Exim's configs in some way (I can't believe Exim wouldn't support PIPENING..).
I have always interpreted the standard in the way that a client MUST NOT assume that the server supports pipelining before it has advertised PIPELINING. Since PIPELINING is only advertised after the client has identified itself as being ESMTP compliant by saying EHLO instead of HELO, I believe that the client MUST wait with his EHLO until the server has shown its banner.
Forcing synchronization is a very effective means of spam protection since most spam bots just blast away with EHLO, MAIL FROM without bothering to wait for the server's banner.
Greetings Marc
--
Marc Haber | "I don't trust Computers. They | Mailadresse im Header Mannheim, Germany | lose things." Winona Ryder | Fon: *49 621 31958061 Nordisch by Nature | How to make an American Quilt | Fax: *49 621 31958062