Re: How to restrict outgoing email to local/company domain only?

Taylor, Grant wrote:
I don't know if it is possible or not to get Sendmail to NOT relay for the host that it is running on. If this is possible, you could remove all domains from class w (local-host-names) and add your domain name to class R (relay-domains). This way, your Test / Development / QA servers would only relay for your main domain name. This would work if your main domain name is not housed on the systems you want restricted. The idea being to allow your systems to relay ONLY for your production domain. Though I'm not sure how to get Sendmail to not relay for local host. Does any one have any suggestions?

Something else you could do is configure your Test / Development / QA servers to SmartHost via your production mail server. Configure your mail server to not relay (class R) for the Test / Development / QA servers. This will allow your Test / Development / QA servers to send email to your domain via the SmartHost but reject any thing not to your domain when your local MTAs talk to the SmartHost. Thus when the local MTA tries to hand off the message to the SmartHost, the SmartHost should reject the message with a permanent error thus causing your local MTA to bounce the original message.



Grant. . . .
.

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