SMTP 500 Syntax error, command unrecognised

[Tibor Borbely]

Hi There,

We had a problem with one SMG server.

Quite often drop messages from GMAIL with SMTP 500 Syntax error code.

 

The main problem we can't check the messages, because there don't get to the Brightmail.

We stopped one SMG server from the four and it solve the problem, but after the restart the problem came up again.

 

What can cause the error ?

And how to capture the dropped messages?

Can check somewhere if the message arrived to the SMG server?

[alexander smg]

If you login to the cli with support account you can run sudo tcpdump. Then grep the output for Gmail connections, or even better just do a pcap, save it on the smg scanner, then download to your desktop with Wireshark to see what is happening. I am curious if your smg is blocking the connection at time of connection.

[Jayesh Rana]

I don't use Protocol control and I haven't intalled it!!!

But when I connect in ssh on my UT I don't have this message!!!!

The problem appear only when I establish a session from the internet!!!

Here is my config:

ISP-ROUTER ---> UT-BRIDGED ---> FIREWALL(ASA) ---> LAN

When I connect from the LAN here is the log:

 

220 mail.my-domain.com Microsoft ESMTP MAIL Service, Version: 6.0.3790.
3959 ready at Thu, 8 Oct 2009 11:21:45 +0200
helo
250 mail.my-domain.com Hello [172.16.4.19]

Or

 

220 mail.my-domain.com Microsoft ESMTP MAIL Service, Version: 6.0.3790.
3959 ready at Thu, 8 Oct 2009 11:22:39 +0200
ehlo
250-mail.my-domain.com Hello [172.16.4.19]
250-TURN
250-SIZE
250-ETRN
250-PIPELINING
250-DSN
250-ENHANCEDSTATUSCODES
250-8bitmime
250-BINARYMIME
250-CHUNKING
250-VRFY
250-X-EXPS GSSAPI NTLM LOGIN
250-X-EXPS=LOGIN
250-AUTH GSSAPI NTLM LOGIN
250-AUTH=LOGIN
250-X-LINK2STATE
250-XEXCH50
250 OK

Her is the log when I establish a session from UT. In my case, telnet session crosses my firewall.

 

220 **************************************************************************************************************************
helo
250 mail.my-domain.com Hello [172.31.1.10]

Or with the ehlo:

 

220 **************************************************************************************************************************
ehlo
250-mail.my-domain.com Hello [172.31.1.10]
250-XXXA
250-SIZE
250-ETRN
250-PIPELINING
250-DSN
250-ENHANCEDSTATUSCODES
250-8bitmime
250-BINARYMIME
250-XXXXXXXB
250-VRFY
250-XXXXXXXXXXXXXXXXXXXXXXXC
250-XXXXXXXXXXXD
250-AUTH GSSAPI NTLM LOGIN
250-AUTH=LOGIN
250-XXXXXXXXXXXE
250-XXXXXXF
250 XG

So it is not my firwall because telnet from UT not display this error.

I'm not using Protocol Control.

Any idea?

[alexander smg]

Why do you have authentication turned on???