DNS (NS) Delegation Record Question 1

[anawrocki]

I am hoping sombody has some real world experience with this and can tell me if I am going in completely the wrong direction.

The question is, can I use a NS record for delegation instead of an A record for a specific node/host name, and then have a DNS server that the NS record points to resolve the name. I hope my question makes sense. I know you can do somthing simular with sub-domains.

The application is going to be used for a Radware Link Proof appliance to provide fail-over with multihomed ISPs, so if anyone has any real world experience setting one of these up I would also appreciate any advice there as well.

 

[ChrisAC]

The server that delegates the sub-domain would usually have NS records for the name server being delegated to and A records to resolve that hostname so that the delegated server can be reached. These a called glue records.

If you just delegate with an NS record(s) but don't resolve that host then that host cannot be resolved to query it and resolve its own name. It's kind of a chicken and the egg situation. That is why glue records are used.

Chris.

**********************
Chris A.C, CCNA, CCSA
**********************

 

[anawrocki]

Got it, makes sense. Is it acceptable in DNS speak to then consider the corresponding

http://www part

of

http://www.domain.com

a sub-domain even though it realy is a single node?

 

[ChrisAC]

That would really be a node within the domain.com zone. You could delegate the

http://www.domain.com

zone as a sub-zone but unless you were going to create more records with node.

http://www.domain.com

then there wouldn't really be much point.

Chris.

**********************
Chris A.C, CCNA, CCSA
**********************

 

[anawrocki]

I think I got it. The point of delegating is that the Radware appliance mentioned above has a built in DNS server, it will answer DNS queries based rules that I define. Say for instance if ISP1's link meets a condition I define (down or high load) the appliance will answer the DNS query with a IP address from ISP2. I am going to use it as an alternative to BGP.

The Radware device can not handle all DNS funtions (MX Records for instance) so I can not use the device for all DNS needs.

Thanks Again