Solved

Reverse zone for a /21 ?

Posted on 2008-06-09
11
219 Views
Last Modified: 2010-04-21
Hello everybody,

I have a /21 PI address space .. which I'll soon get master access for ( tomorrow or so ) and I was wondering how would the zone file for ISC's bind/named would look like for a /21 (reverse entries)..  the config file...

Thanks in advance.
0
Comment
Question by:michaeljohn00
[X]
Welcome to Experts Exchange

Add your voice to the tech community where 5M+ people just like you are talking about what matters.

  • Help others & share knowledge
  • Earn cash & points
  • Learn & ask questions
  • 6
  • 5
11 Comments
 
LVL 71

Accepted Solution

by:
Chris Dent earned 250 total points
ID: 21749573

Reverse Lookup Zones are Classful only, if it's a Private IP Range you'd be better served by adding a /16 zone. If you wish to split it you'd have to create /24's for each member of the /21.

Any reference to Classless is for Classless delegation which is possible, but is more of a work-around within Classful zones.

HTH

Chris
0
 

Author Comment

by:michaeljohn00
ID: 21749987
So I'll have to add 7 /24 zones for each class in the 21 ?

zone "t.b.a.in-addr.arpa" {
        type master;
        notify no;
        file "zone/a.b.t.zone";
};

zone "u.b.a.in-addr.arpa" {
        type master;
        notify no;
        file "zone/a.b.u.zone";
};

zone "v.b.a.in-addr.arpa" {
        type master;
        notify no;
        file "zone/a.b.v.zone";
};

zone "w.b.a.in-addr.arpa" {
        type master;
        notify no;
        file "zone/a.b.w.zone";
};

.... ?
0
 
LVL 71

Expert Comment

by:Chris Dent
ID: 21750042

Afraid so, yes. Unless you go up and add the single /16 (b.a.in-addr.arpa).

Chris
0
Technology Partners: We Want Your Opinion!

We value your feedback.

Take our survey and automatically be enter to win anyone of the following:
Yeti Cooler, Amazon eGift Card, and Movie eGift Card!

 

Author Comment

by:michaeljohn00
ID: 21750122
any disadvantages if I go to a B class ?
0
 
LVL 71

Expert Comment

by:Chris Dent
ID: 21750169

It makes your DNS server authoritative for the /16 range, that may be a problem if you need to resolve addresses outside of the scopes you've posted above.

If you don't have any other ranges then it's not a problem.

Chris
0
 

Author Comment

by:michaeljohn00
ID: 21750207
no, I'll only need to resolve for my /21 .. I'm not authoritative for any others.
0
 

Author Closing Comment

by:michaeljohn00
ID: 31465600
Thanks again.
0
 
LVL 71

Expert Comment

by:Chris Dent
ID: 21750235

Hmm then it's probably best to add them as /24 zones. Less chance of something going wrong.

The disadvantage of that is it's more effort to manage.

Chris
0
 

Author Comment

by:michaeljohn00
ID: 21750254
Neah, I'll just have to add them once .. I don't plan changing the ptrs daily ! :) I can easily make a shell script or something to generate all the files and stuff ..

how would the container of the zone look like ?

--- got from tldp's dns how to... how should ns.linux.bogus & master.linux.bogus. look like here ?

$TTL 3D
@       IN      SOA     ns.linux.bogus. hostmaster.linux.bogus. (
                        199802151 ; Serial, todays date + todays serial
                        8H      ; Refresh
                        2H      ; Retry
                        4W      ; Expire
                        1D)     ; Minimum TTL
                NS      ns.linux.bogus.

1               PTR     gw.linux.bogus.
2               PTR     ns.linux.bogus.
3               PTR     donald.linux.bogus.
4               PTR     mail.linux.bogus.
5               PTR     ftp.linux.bogus.
0
 
LVL 71

Expert Comment

by:Chris Dent
ID: 21750449

That all looks fine, the NS records are perfect :)

Chris
0
 

Author Comment

by:michaeljohn00
ID: 21751689
might be .. but .. --- got from tldp's dns how to.
. how should ns.linux.bogus & master.linux.bogus. look like here ?
0

Featured Post

On Demand Webinar - Networking for the Cloud Era

This webinar discusses:
-Common barriers companies experience when moving to the cloud
-How SD-WAN changes the way we look at networks
-Best practices customers should employ moving forward with cloud migration
-What happens behind the scenes of SteelConnect’s one-click button

Question has a verified solution.

If you are experiencing a similar issue, please ask a related question

Suggested Solutions

Meet the world's only “Transparent Cloud™” from Superb Internet Corporation. Now, you can experience firsthand a cloud platform that consistently outperforms Amazon Web Services (AWS), IBM’s Softlayer, and Microsoft’s Azure when it comes to CPU and …
If you're not part of the solution, you're part of the problem.   Tips on how to secure IoT devices, even the dumbest ones, so they can't be used as part of a DDoS botnet.  Use PRTG Network Monitor as one of the building blocks, to detect unusual…
This video gives you a great overview about bandwidth monitoring with SNMP and WMI with our network monitoring solution PRTG Network Monitor (https://www.paessler.com/prtg). If you're looking for how to monitor bandwidth using netflow or packet s…
In this tutorial you'll learn about bandwidth monitoring with flows and packet sniffing with our network monitoring solution PRTG Network Monitor (https://www.paessler.com/prtg). If you're interested in additional methods for monitoring bandwidt…

730 members asked questions and received personalized solutions in the past 7 days.

Join the community of 500,000 technology professionals and ask your questions.

Join & Ask a Question