topic Re: DNS Reverse lookup in Operating System - HP-UX

DNS Reverse lookup

Mark Seida — Wed, 06 Jun 2001 15:16:49 GMT

I am setting up dns in a closed network with subdomains there is no contact with any root servers. I modified the db.cache file to make it the root server. I am running bind 4.9.7 on hpux 11.00. The root server is .com and then I have mn..com and be..com are the subdomains. I can do forward name resolution but not reverse. Any sugestions would be appriated.

Re: DNS Reverse lookup

Vincenzo Restuccia — Wed, 06 Jun 2001 15:33:15 GMT

See http://docs.hp.com/cgi-bin/fsearch/framedisplay?top=/hpux/onlinedocs/J2776-90008/J2776-90008_top.html&con=/hpux/onlinedocs/J2776-90008/00/00/20-con.html&toc=/hpux/onlinedocs/J2776-90008/00/00/20-toc.html&searchterms=dns&queryid=20010606-093209

Re: DNS Reverse lookup

Kevin Wright — Wed, 06 Jun 2001 16:00:14 GMT

are your PTR records set up? probably not. You should really be using a newer bind, but regardless, do you have both forward and reverse zone files defined in named.conf..boot for you.

Re: DNS Reverse lookup

Mark Seida — Wed, 06 Jun 2001 16:01:36 GMT

All servers are running HPUX 11.00 and we are not trying to create load balancing. I am just trying to get reverse name resolution to work. The online help was somewhat helpful but it still has not shown me enough that I can solve the problem. I think the problem has to do with the db.192.168. since this is a private address network. The root server is on one of the class c subnets and I think it has to do with the fact the root server has a 168.192.IN-ADDR.ARPA which would make it think that all of the subnets are in its domain so it should have the entries in its db.192.168 file. But the problem is it resides on the same subnet as the mn..com domain.

Re: DNS Reverse lookup

Mark Seida — Wed, 06 Jun 2001 16:13:03 GMT

I have the ptr records in the db.. Do I need some sort of entry in the revese db.192.168?

Re: DNS Reverse lookup

Kamlesh Shete — Wed, 06 Jun 2001 18:40:51 GMT

You should add ptr entries in the db.192.68

- KS

Re: DNS Reverse lookup

Mark Seida — Wed, 06 Jun 2001 19:15:34 GMT

The ptr records are in the db.192.168 file and I still have a problem doing reverse name resolution.

Re: DNS Reverse lookup

Jordan Bean — Wed, 06 Jun 2001 23:06:06 GMT

BIND 4.9.7... yuck. Try 8.9.3.

nslookup -type=soa 168.192.in-addr.arpa. ?
Is the zone configured in named.boot?
Does the serial for the zone need to be incremented?
Is the zone properly delegated?
Was named HUP'd?

Re: DNS Reverse lookup

Wilfred Chau_1 — Fri, 08 Jun 2001 20:43:06 GMT

Did you try to use hosts_to_named?
If not, create a /etc/named.data directory.
create a file called param, or anything.
add this to param.
-d .com
-s your name server
-n 192.168
-d mn..com
-n ?.?
-d be..com
-n ?.?
-r your name server

Save the file, and do this,
cd /etc/named.data; hosts_to_named -f param
sig_named restart

Re: DNS Reverse lookup

Jordan Bean — Fri, 08 Jun 2001 22:13:00 GMT

I'm tyring to visualize the setup:

In this isolated network, how many name servers are you running? Just the one root master? Or does each subdomain have a master server?

If just the one, the issue should be fairly trivial. The zone file for 168.192.in-addr.arpa would look like this:

$ORIGIN 168.192.in-addr.arpa.
@ IN SOA host.domain.com. hostmaster.domain.com. ( a b c d e )
IN NS host.domain.com.
1.1 IN PTR host.domain.com.
2.1 IN PTR host.mn.domain.com.
2.2 IN PTR host.be.domain.com.

But if you're maintaining the subdomains separately on other servers, then the root needs to delegate from both zones:

$ORGIN domain.com.
@ IN SOA ...
IN NS host.domain.com.
host IN A 192.168.1.1
mn IN NS host.mn.domain.com.
host.mn IN A 192.168.1.2
be IN NS host.be.domain.com.
host.be IN A 192.168.2.2

$ORIGIN 168.192.in-addr.arpa.
@ IN SOA ...
IN NS host.domain.com.
1.1 IN PTR host.domain.com.
1 IN NS host.mn.domain.com.
2.1 IN PTR host.mn.domain.com.
2 IN NS host.be.domain.com.
2.2 IN PTR host.be.domain.com.

I typed this up pretty quick so I'd expect errors.