[DNS] Reverse Lookup for 2 IP Addresses

Originally I had the server at home and on Comcast so I used dyndns.org for DNS.

Once the server got a bit more popular, I leased a server at a colo facility. They set up the server name in their DNS so I didn't really have any reason to manage my own DNS. DynDNS was managing the domains and I had a reverse lookup for the server so mail was being delivered.

Recently I upgraded server to a more powerful server and this time they didn't add the server to their DNS. When I asked them about it, they offered to manage my DNS for me for a few bucks per domain or they'd delegate it to me.

I checked DynDNS and they'll manage the reverse lookup but it's a few extra bucks. May as well have the ISP manage it as it's a few bucks less if I go that way.

But I've administered bind in the past for entire address ranges so rather than pay someone else to manage it, I'd rather do it myself. Both to save a few bucks but also to keep my fingers in DNS management.

So I got my domain files set up without a problem but I'm not sure how to set up a reverse lookup file for a single or two addresses. I want to make sure it's right before I flip the switch so I thought I'd drop a quick note here and see what sort of response I get :slight_smile:

# cat 172.111.65.in-addr.arpa
$ORIGIN .
$TTL 86400      ; 1 day
172.111.65.IN-ADDR.ARPA IN      SOA ns1.youreadumbass.org. hostmaster.schelin.org. (
                                1               ; serial
                                10800           ; refresh (3 hours)
                                3600            ; retry (1 hour)
                                604800          ; expire (1 week)
                                3600            ; minimum (1 hour)
                                )
                IN      NS      ns1.youreadumbass.org.

$ORIGIN 172.111.65.IN-ADDR.ARPA.
167             IN      PTR     youreadumbass.org.
168             IN      PTR     youreadumbass.org.

Ultimately I believe I'd have the same two PTR records for each of the domains. And I'll contact the ISP to delegate the two IP's to my control with them as my secondary or maybe DynDNS.

So, opinions? Suggestions? Go read the Cricket book? :slight_smile:

Thanks.

Carl

Carl, your approach seems correct, as well as PTR section. I can't find any gotchas it first glance, I think you're ready to go, certainly, other opinions are appreciated as always.

Just out of curiosity, will they delegate the whole of 172.111.65.IN-ADDR.ARPA. to you so you can serve out just two addresses, or how does this fit into the big picture?

(Should you have a full stop after "arpa" on the first occurrence?)

I used another arpa file as a template and it apparently didn't have it, but I'll check my Cricket book just to be sure.

And they're just going to give me the two addresses. That was where I had the question. Is it really just a file and I can call it whatever I want or does it actually affect the entire range. I wasn't sure if I should have two arpa files:

# cat 167.172.111.65.in-addr.arpa
$ORIGIN .
$TTL 86400      ; 1 day
167.172.111.65.IN-ADDR.ARPA IN      SOA ns1.youreadumbass.org. hostmaster.schelin.org. (
                                1               ; serial
                                10800           ; refresh (3 hours)
                                3600            ; retry (1 hour)
                                604800          ; expire (1 week)
                                3600            ; minimum (1 hour)
                                )
                IN      NS      ns1.youreadumbass.org.

$ORIGIN 167.172.111.65.IN-ADDR.ARPA.
167             IN      PTR     youreadumbass.org.
# cat 168.172.111.65.in-addr.arpa
$ORIGIN .
$TTL 86400      ; 1 day
168.172.111.65.IN-ADDR.ARPA IN      SOA ns1.youreadumbass.org. hostmaster.schelin.org. (
                                1               ; serial
                                10800           ; refresh (3 hours)
                                3600            ; retry (1 hour)
                                604800          ; expire (1 week)
                                3600            ; minimum (1 hour)
                                )
                IN      NS      ns1.youreadumbass.org.

$ORIGIN 168.172.111.65.IN-ADDR.ARPA.
168             IN      PTR     youreadumbass.org.

I think that's really where the question comes in.

Carl

No, you definitely want them both in a single zone 172.11.65.in-addr.arpa. My question is whether your ISP is really going to delegate authority for the whole zone (254 addresses) to you so that you can serve reverse DNS for two of the addresses in it, or do you give your zone file to the guys who have the authority, and they merge it with theirs (in which case you need to know what they need, not what BIND eventually will need).

From what I recall, the options were that they'd manage the two IP's for me, or they'd delegate them to either me or to a third party. If they delegate the entire range to me then I'm good on managing a range, basically the first item I posted. I'll have to check the e-mail again and see exactly what they were offering.

Carl

The e-mail I received:

I'm wondering if they're really not going to delegate the two IP's to me and are just talking about A records and not PTR records. I'll have to query them and see what the next step is. I have the A record side ready to go. It's the PTR's that need to work properly for e-mail to be accepted by AOL, Inbox.com, Comcast.Net, and others that are refusing due to a failed reverse lookup.

Carl

That's what it sounds like to me. Or rather, the email probably doesn't want to talk about reverse DNS at all (and if I were them I would not want to talk about it :slight_smile:

Some places set up indirections so they can delegate subspaces of a reverse DNS range but if they don't offer you this service up front, they probably don't have it set up that way.