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Re: "cannot find your hostname", but DNS lookups are fine

From: Robert Felber (r.felberek-muc.de)
Date: Wed Oct 12 2005 - 02:00:39 CDT

On Wed, Oct 12, 2005 at 04:51:37PM +1000, Ben Finney wrote:
> Howdy all,
>
> I use 'smtpd_recipient_restrictions = reject_unknown_hostname'. I get
> mail from most places I expect to work, but one particular
> correspondent is being rejected:
>
> =====
> Oct 12 14:37:37 protea postfix/smtpd[32733]: NOQUEUE: reject: RCPT from unknown[150.101.164.6]: 450 Client host rejected: cannot find your hostname, [150.101.164.6]; from=<squawkcorax.com.au> to=<benbenfinney.id.au> proto=ESMTP helo=<nest.corax.com.au>
> =====
>
> Yet the host reverse-map seems fine:
>
> =====
> $ host 150.101.164.6
> 6.164.101.150.in-addr.arpa domain name pointer eth164-6.vic.adsl.internode.on.net.
>
> If these DNS lookups work fine, why is Postfix rejecting this host
> with "cannot find your hostname"?

%host eth164-6.vic.adsl.internode.on.net
Host eth164-6.vic.adsl.internode.on.net not found: 3(NXDOMAIN)

Thus it fails.

--
    Robert Felber (PGP: 896CF30B)
    Munich, Germany
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