Page 1 of 1

Cannot find your hostname

Posted: Thu Jul 12, 2018 8:17 pm
by sebiuo
Hello, this is my first post i already read a lot in here but cant resolve this.

i have this problem, when i send emails from my server.
it has this network config:
private ip: 10.10.1.54
public ip: 200.14.251.248


sebiuo@~$ nslookup 200.14.251.248
Server: 127.0.0.1
Address: 127.0.0.1#53
Non-authoritative answer:
248.251.14.200.in-addr.arpa name = mail.tehmcorp.cl.

sebiuo@~$ nslookup mail.tehmcorp.cl
Server: 127.0.0.1
Address: 127.0.0.1#53
Non-authoritative answer:
Name: mail.tehmcorp.cl
Address: 200.14.251.248

But i got this message, and when i send emails it says that my ip is 200.14.251.247 (my wan)

"Your IP address 200.14.251.247 is associated with the domain rdc-net251.zone.
Nevertheless your message appears to be sent from mail.tehmcorp.cl.
You may want to change your pointer (PTR type) DNS record and the host name of your server to the same value.
Here are the tested values for this check:

IP: 200.14.251.247
HELO: mail.tehmcorp.cl
rDNS: rdc-net251.zone "

What i'm missing? :?

Re: Cannot find your hostname

Posted: Fri Jul 13, 2018 12:17 am
by fs.schmidt
Hi,

It seems that your DNS hasn't replicated:

nslookup 200.14.251.247

Nome: rdc-net251.zone
Address: 200.14.251.247

Re: Cannot find your hostname

Posted: Fri Jul 13, 2018 12:47 pm
by sebiuo
fs.schmidt wrote:Hi,

It seems that your DNS hasn't replicated:

nslookup 200.14.251.247

Nome: rdc-net251.zone
Address: 200.14.251.247
but my public ip is 200.14.251.248, .247 is my wan to internet.
:|

Re: Cannot find your hostname

Posted: Fri Jul 13, 2018 1:15 pm
by phoenix
sebiuo wrote:
fs.schmidt wrote:Hi,

It seems that your DNS hasn't replicated:

nslookup 200.14.251.247

Nome: rdc-net251.zone
Address: 200.14.251.247
but my public ip is 200.14.251.248, .247 is my wan to internet.
:|
Do you also have a Split DNS configured?

Re: Cannot find your hostname

Posted: Fri Jul 13, 2018 2:27 pm
by sebiuo
phoenix wrote:
sebiuo wrote:
fs.schmidt wrote:Hi,

It seems that your DNS hasn't replicated:

nslookup 200.14.251.247

Nome: rdc-net251.zone
Address: 200.14.251.247
but my public ip is 200.14.251.248, .247 is my wan to internet.
:|
Do you also have a Split DNS configured?
I got bind9 installed, i missing something in there?
i use dnscheck, btw my hostname is mail.tehmcorp.cl

[root@mail ~]# dig tehmcorp.cl mx

; <<>> DiG 9.8.2rc1-RedHat-9.8.2-0.62.rc1.el6_9.5 <<>> tehmcorp.cl mx
;; global options: +cmd
;; Got answer:
;; ->>HEADER<<- opcode: QUERY, status: NOERROR, id: 63794
;; flags: qr aa rd ra; QUERY: 1, ANSWER: 1, AUTHORITY: 1, ADDITIONAL: 2

;; QUESTION SECTION:
;tehmcorp.cl. IN MX

;; ANSWER SECTION:
tehmcorp.cl. 1 IN MX 0 mail.tehmcorp.cl.

;; AUTHORITY SECTION:
tehmcorp.cl. 1 IN NS ns1.tehmcorp.cl.

;; ADDITIONAL SECTION:
mail.tehmcorp.cl. 1 IN A 200.14.251.248
ns1.tehmcorp.cl. 1 IN A 200.14.251.248

;; Query time: 0 msec
;; SERVER: 127.0.0.1#53(127.0.0.1)
;; WHEN: Fri Jul 13 11:02:20 2018
;; MSG SIZE rcvd: 100


[root@mail ~]# dig tehmcorp.cl

; <<>> DiG 9.8.2rc1-RedHat-9.8.2-0.62.rc1.el6_9.5 <<>> tehmcorp.cl
;; global options: +cmd
;; Got answer:
;; ->>HEADER<<- opcode: QUERY, status: NOERROR, id: 41183
;; flags: qr aa rd ra; QUERY: 1, ANSWER: 1, AUTHORITY: 1, ADDITIONAL: 1

;; QUESTION SECTION:
;tehmcorp.cl. IN A

;; ANSWER SECTION:
tehmcorp.cl. 1 IN A 200.14.251.248

;; AUTHORITY SECTION:
tehmcorp.cl. 1 IN NS ns1.tehmcorp.cl.

;; ADDITIONAL SECTION:
ns1.tehmcorp.cl. 1 IN A 200.14.251.248

;; Query time: 0 msec
;; SERVER: 127.0.0.1#53(127.0.0.1)
;; WHEN: Fri Jul 13 10:39:11 2018
;; MSG SIZE rcvd: 79

Re: Cannot find your hostname

Posted: Fri Jul 13, 2018 3:01 pm
by phoenix
You're using the wrong command (the domain name part of your dig) and you appear to be getting the wrong answer, it should return the LAN IP of your mail server. Go to the Split DNS wiki article and run all the commands shown in the "Verify....." section of that article. Read the text in that section and it tells you what to expect for the correct output of those commands.