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Re: [Fwd: Postfix SMTP server: errors from unknown[63.64.27.245]]

From: Len Conrad (LConradGo2France.com)
Date: Fri Jul 02 2004 - 07:53:38 CDT

>I don't see how this could have been blocked on the bases of hostname.

it wasn't

>I can do a lookup of all the hlgllc.com addresses for both MX and A
>records, but the 'dig -x' one doesn't make much sense.

do DNS queries with dig, not nslookup

>But it appears that doing a lookup against this one (host245.hlgllc.com)
>does seem to fail.

yep, nxdomain:

dig host245.hlgllc.com any

; <<>> DiG 9.2.3rc3 <<>> host245.hlgllc.com any
;; global options: printcmd
;; Got answer:
;; ->>HEADER<<- opcode: QUERY, status: NXDOMAIN, id: 10950
;; flags: qr rd ra; QUERY: 1, ANSWER: 0, AUTHORITY: 1, ADDITIONAL: 0

;; QUESTION SECTION:
;host245.hlgllc.com. IN ANY

;; AUTHORITY SECTION:
hlgllc.com. 10765 IN SOA nsmain.microman.net.
admin.microman.net. 2002040803 43200 7200 86400 172800

> What I'm surprised at is the report that it cannot find a hostname for
> 63.64.27.245.

# dig -x 63.64.27.245

; <<>> DiG 9.2.3rc3 <<>> -x 63.64.27.245
;; global options: printcmd
;; Got answer:
;; ->>HEADER<<- opcode: QUERY, status: NOERROR, id: 12798
;; flags: qr rd ra; QUERY: 1, ANSWER: 2, AUTHORITY: 2, ADDITIONAL: 2

;; QUESTION SECTION:
;245.27.64.63.in-addr.arpa. IN PTR

;; ANSWER SECTION:
245.27.64.63.in-addr.arpa. 21494 IN CNAME 245.240.27.64.63.in-addr.arpa.
245.240.27.64.63.in-addr.arpa. 21494 IN PTR host245.hlgllc.com.

>What am I missing?

... that postfix PTR validation requires the PTR domain name have an A
record that matches.

63.64.27.245 doesn't so, postfix reports "(PTR) hostname (with matching A
record) not found."

Len

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