Does mailx send mail using an SMTP relay or does it directly connect to the target SMTP server?

Posted by iamrohitbanga on Super User See other posts from Super User or by iamrohitbanga
Published on 2010-05-04T13:17:09Z Indexed on 2010/05/04 13:19 UTC
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Filed under:

linux

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mailx

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smtp

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nat

Suppose i send a mail using the following the following command:

mailx [email protected]

then does mailx first try to find out the SMTP server of my ISP for relaying the mail or does it connect directly. Does it depend on whether my PC has a public IP address or it is behind a NAT. How do I check the settings of mailx on my PC? How can I verify this using tcpdump?

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