On 09/24/2011 01:22 PM, Steve Weigold wrote: > > Greetings everyone, > > I'm testing a postfix install on a machine on my local lan. Although I > don't expect it to be relevant to the problem, it's an embedded debian > system. Postfix is configured to relay through an ISP email server to > send outgoing emails (ie relayhost = my.isp.server). Currently, it's > set to accept SMTP from the local network (mynetworks = 192.168.200.0/24 > 127.0.0.0/8). > > If I telnet to localhost and send the commands to create an email to an > outside domain, the email is created and properly delivered. System > emails on the system are forwarded to an outside domain using root > aliased to a local user aliased to an email address. This is also > working. As such, I believe outgoing email functions properly. > Further, if I telnet to the machine from a debian linux box on the > subdomain and repeat the process, this also works properly. > > I've noticed two issues: > > First, if I telnet to the machine from a windows box, I receive the > greeting from the box, but there seems to be something corrupted in that > the first command I send seems to be ignored until I send a second > <enter> which I assume translates to <crlf>. At that point, I get a bad > syntax message from the box. Further commands function properly though > and the email is created and sent as expected.
Some anti-virus solution include a SMTP proxy that can break the dialogue in a similar way. I've seen some McAfee versions doing something like this (https://kc.mcafee.com/corporate/index?page=content&id=KB50707). Simon > Second, I have thunderbird (on the same windows box) configured to use > the same outgoing SMTP connection for testing. No authentication, port > 25... etc. Sending emails in this fashion times out. > > Wireshark monitoring of the transaction between thunderbird and the > embedded box finds that the connection is made properly, the box issues > the greeting, and the windows machine sends the TCP ACK to the 220 > greeting message. Other than that though, there is no response from > the windows box or thunderbird specifically to the 220 greeting until > thunderbird gives up and I see the FIN and FIN, ACK TCP messages. > > I suspect the two observations are related, but thats as far as I've > been able to get. > > Any help? > > I also should note that I also installed and maintain an email server > running postfix on debian linux handling a dozen virtual domains. I > didn't have this problem there, so I don't think it's some kind of > windows incompatibility as much as I'd like to blame windows :) > > Steve >