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I have a web server that talks to a mail server when sending an email. Now I'm hosting my own DNS, however, since then I see that one of the email headers says:

Received: from (unknown [])

where has the IP and the router where is connected has, before I used to see the hostname of (

In the 192.168.0.rev zone I have: IN PTR

and has: router IN A

/etc/resolv.conf on the web/mail server:

nameserver ISP address

Am I missing something? Thanks!

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You probably also need to put a PTR entry into your local zone for like IN PTR The message you see indicates that your mail server (presumably running on does not recogmise a valid PTR record for Though, I would expect the header to read: Received: from (unknown []) ...

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I tried adding a PTR entry as you mentioned, however, still same thing. BTW, I'm using a sendmail emulation to talk to the mail server. – Mike Darrow Jul 14 '11 at 14:39
Where is the mail server installed, does the mail server run on, or is the mail server external to your network? – Mike Insch Jul 14 '11 at 15:27

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