smtp outgoing problae.

[shahjahan]

Hello All.

I have a centos v5.5 server, postfix service runing and work Properly.

when i out of office then i Received my mail but not send.


( when i out of office use mobile internet)

please help me.
Md.shahjahan

[Matti_Kurkela · Accepted solution]

Welcome to ITRC Forums!

Your question is not clear. Do you carry your server around when you're out of office? (With a virtual machine on your laptop, this is certainly possible.)

Or are you trying to use some mobile device to connect to your server, which is in the office?

Many Internet Service Providers only allow you to connect to their own mail server when sending mail with a consumer-grade connection, so that they can filter out viruses (= stop one infected system from infecting others) and detect if someone is sending out massive amounts of junk mail. If the message passes through the checks, the ISP's mail server will automatically forward the messages to their destination.

Technically, this is implemented by blocking outgoing TCP connections to port 25, to any destination host other than the ISP's mail server.

Enterprise-grade connections are usually not restricted, so the server(s) in your office can send mail anywhere.

If your mobile internet service provider has such a restriction, you must use a different SMTP server setting in your email program when you're out of office.

If your mobile device is capable of using the "submission" protocol as described by RFC4409 (= authenticated, TLS-encrypted SMTP), you might be able to use this to connect to the mail server in your office.

Depending on your situation, this part of the Postfix documentation might be a good place to start:
http://www.postfix.org/SASL_README.html


MK