Deferred while performing the EHLO handshake

[joyfulway]

Hi,

our Zimbra server has been running for almost 2 years without major issue.

Two days ago, we were unable to send outgoing mail.

/var/log/zimbra.log gives:

Oct 14 11:22:17 mailserver postfix/smtp[15130]: E98B0DA8153: to=<xxxx@gmail.com>, relay=41.204.XX.YY[41.204.XX.YY]:25, delay=0.16, delays=0.01/0.01/0.13/0, dsn=4.4.2, status=deferred (lost connection with 41.204.XX.YY[41.204.XX.YY] while performing the EHLO handshake)

I'm using my isp smtp server for outgoing mail: 41.204.XX.YY 25 which used to work perfectly.

My Zimbra server settup is:
Web mail MTA Hostname : mailserver.xxx.com
Relay MTA for external delivery : 41.204.XX.YY 25
DNS lookups ticked

Does anyone ever experienced this EHLO handshake issue ?

Thanks,
sngome

Zimbra : Release 5.0.8_GA_2462.RHEL4_20080709163257 RHEL4 FOSS edition

[jwilke]

did you try telnetting to your relay server, to see if it is functioning when you type mail commands manually ?

like this:

SMTP Telnet

could very well be a problem at your ISP

[joyfulway]

Hi,

thanks. Will try it.

so far telnet smtp 25 works fine.

[y@w]

I've seen something similar when going through an old Cisco PIX firewall, but typically it's when sending DATA.

Was the ISP support any help? They may have a more helpful error on their end.

It could also be an antivirus on the remote end.

If sending a message via telnet works and all else fails, you could always try putting Postfix into debug mode for that host:
Postfix Debugging Howto

[fhouston]

I just setup a test server again (tried it out about a year or more ago and for various reasons we didn't move over then) and I'm having problems getting mail from our current server to the zimbra server. I don't recall that this was an issue before but perhaps I've forgotten something. Anyway, I'm getting the following error on my postfix/mail machine while trying to send to the zimbra install:

status=deferred (conversation with [ZIMBRA] timed out while performing the EHLO handshake)

Now if I manually telnet from the postfix/mail machine to the zimbra machine and use HELO that works fine and the email goes though. If I manually test w/ EHLO nothing ever happens. So IMHO it seems like zimbra is not recognizing EHLO for some reason.

Any thoughts/hints/clues/suggestions would be appreciated...

TIA