# Reverse DNS on TinyDNS

## r00t440

Hello,

I am subscribed to a DSL internet in my place, with it I've setup various servers like email, web, ftp, ssh, DNS, etc. I managed to setup TinyDNS, and I can create any subdomain under my domain. 

My problem is how to setup reverse DNS lookups on TinyDNS, I'm a little confused. I have a static external IP which is acquired via DHCP. My ISP provided me with only a single IP. Is it possible to setup reverse DNS? I need a little help regarding the matter. Any clue would be highly appreciated.

Please be easy on me, as I am a newbie. I badly need it because I have an email server, and all my mails goes to the spam folder of other email providers like GMail, Yahoomail, Hotmail, etc.

By the way, when I do "dig @111.112.113.114 -x 111.112.113.114" i'm able to get a reply, but of course from outside, it seem to be not working.

```
; <<>> DiG 9.4.1-P1 <<>> @111.112.113.114 -x 111.112.113.114

; (1 server found)

;; global options:  printcmd

;; Got answer:

;; ->>HEADER<<- opcode: QUERY, status: NOERROR, id: 12139

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

;; WARNING: recursion requested but not available

;; QUESTION SECTION:

;114.113.112.111.in-addr.arpa.    IN      PTR

;; ANSWER SECTION:

114.113.112.111.in-addr.arpa. 86400 IN    PTR     mydomain.com.

;; AUTHORITY SECTION:

114.113.112.111.in-addr.arpa. 259200 IN   NS      a.ns.114.113.112.111.in-addr.arpa.

114.113.112.111.in-addr.arpa. 259200 IN   NS      a.ns.114.113.112.111.in-addr.arpa.

;; ADDITIONAL SECTION:

a.ns.114.113.112.111.in-addr.arpa. 259200 IN A    111.112.113.114

a.ns.114.113.112.111.in-addr.arpa. 259200 IN A    111.112.113.114

;; Query time: 1 msec

;; SERVER: 111.112.113.114#53(111.112.113.114)

;; WHEN: Wed Apr  9 20:48:45 2008

;; MSG SIZE  rcvd: 137

```

TIA

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## DarKRaveR

Common sense is, tht the network provier (ip address space provider/owner) is responsible for reverse mapping.

It's same same hierachical concept as for domain names, for example some organisation (let's say ripe) is responsible for let's say: 142.0.0.0/8, then ripe delegates to the addres space owners (ISPs), then smaller ISPs/customers. Now, a Delegation of a single IP just makes hardly sense, you could ask though, if your provider might setup a specific reverse record for your IP (or if they would set up a delegation, which I doubt).

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## r00t440

Hi DarKRaveR,

Thanks for the info. So, if I can ask my ISP to setup a reverse record for my IP, then my problem would be solved? I'll try to ask them, hopefully they'll be kind enough to provide me such extra service. 

Best regards

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## DarKRaveR

Yes, maybe an example can show you, what I am talking about:

 *Quote:*   

> dig +trace -x 209.85.137.99
> 
> ; <<>> DiG 9.4.1-P1 <<>> +trace -x 209.85.137.99
> 
> ;; global options:  printcmd
> ...

 

I have cropped most of the data, to make things easier to catch. As you can see 209.in-addr.arpa (which ist 209.0.0.0/ :Cool:  is delegated to arin (which is responsible for that network block.

ARIN then delegates 137.85.209... (209.85.137.0/24) to google com (which would indicate that google 'owns/administers' at lest the complete 209.85.137.0/24 network).

In fact: 209.85.128.0/17  belongs to google. since CIDR delegations are a little 'nasty' arin obviously delegates each /24 seperately.

So usualy, whenever a provider gives away an IP Block, he usually delegates the reverse lookups for that block to the customer, since he is usually responsible for the usage of the IPs. For a single IP a delegation is usually not done though, that's why[/quote] I think you got bigger chances in asking them to put whatever you want into their reverse zone.

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