Fwd/Rev DNS match

javier.basile · ‎05-20-2013

I am also confused as to the "Fwd/Rev DNS match" not be checked for IP 190.210.112.145

you can see clearly bellow that the PTR and rPTR match, ... .????

MX Record: yes Checked (duh )

exclusive IP yes checked

openDKIM signing checked

SPF 1 and 2 checked

hostname matches the PTR

rPTR matches PTR

so I am really at a loss here. What am I missing ?

kussriva · ‎05-21-2013

Hi,

May it be that the DNS entries have been changed recently? Propagating
changes may require some time on the SenderBase Website?

Regards,
Kush

Stephan Bayer · ‎05-21-2013

Hello Kush,

Please see the example:

http://en.wikipedia.org/wiki/Forward-confirmed_reverse_DNS

"DNS query type PTR on 192.0.2.4 --> returns PTR-record="hostname.example.com" (1 result) DNS query type A on "hostname.example.com" --> returns A-record=192.0.2.4 (1 result) Matches original IP address, therefore check passes"

So for your IP address I checked

190.210.112.145 and received no PTR record:

PTR

No PTR record found.

javier.basile · ‎05-21-2013

Hi, Thanks for the reply.

The company that provides the static ip is iPlan. They configured in the following rDNS PTR 190 210 112 145 isec.edu.ar. Is this okay?

Stephan Bayer · ‎05-22-2013

Hi Javier,

I'm sorry, I don't know enough about your configuration to give you each step by step answer. I've provided a working configuration below.

EXAMPLE OF FWD/REV DNS WORKING Configuration

-----------------------------------------

beeze@bzlubuntu:~$ host cisco.com <<< --- START WITH DOMAIN NAME

cisco.com has address 72.163.4.161

cisco.com has IPv6 address 2001:420:1101:1::a

cisco.com mail is handled by 15 alln-mx-01.cisco.com.

cisco.com mail is handled by 15 ams-mx-01.cisco.com.

cisco.com mail is handled by 10 rcdn-mx-01.cisco.com. <<< - PICK AN MX Record

cisco.com mail is handled by 15 rtp-mx-01.cisco.com.

beeze@bzlubuntu:~$ host rcdn-mx-01.cisco.com

rcdn-mx-01.cisco.com has address 72.163.7.166 << GET IP OF MX HOSTNAME

beeze@bzlubuntu:~$ host 72.163.7.166

166.7.163.72.in-addr.arpa domain name pointer rcdn-mx-01.cisco.com. << CONFIRM PTR Record exists

beeze@bzlubuntu:~$ dig rcdn-mx-01.cisco.com << PERFORM A Record Lookup on the MX RECORD

; <<>> DiG 9.9.2-P1 <<>> rcdn-mx-01.cisco.com

;; global options: +cmd

;; Got answer:

;; ->>HEADER<<- opcode: QUERY, status: NOERROR, id: 17084

;; flags: qr aa rd ra; QUERY: 1, ANSWER: 1, AUTHORITY: 2, ADDITIONAL: 3

;; OPT PSEUDOSECTION:

; EDNS: version: 0, flags:; udp: 4096

;; QUESTION SECTION:

;rcdn-mx-01.cisco.com. IN A

;; ANSWER SECTION:

rcdn-mx-01.cisco.com. 86400 IN A 72.163.7.166 << Confirm that it matches

;; AUTHORITY SECTION:

cisco.com. 86400 IN NS ns1.cisco.com.

cisco.com. 86400 IN NS ns2.cisco.com.

;; ADDITIONAL SECTION:

ns1.cisco.com. 600 IN A 72.163.5.201

ns2.cisco.com. 86400 IN A 64.102.255.44

;; Query time: 7 msec

;; SERVER: 127.0.1.1#53(127.0.1.1)

;; WHEN: Wed May 22 08:20:58 2013

;; MSG SIZE rcvd: 133