ns record problem

[Kevin Darcy]

Alex Tang wrote:

>Hi all
>Sometimes I cannot send email to a domain and find out the problem may
>be caused by some dns setting of the domain.
>ref:
>my bind version is bind 8.37 and bind 9, and sendmail 
>
>I have a interest porblem about resolve result of ns record.
>A domain aplus-beto.com.tw whois authoritative name server are:
>
>
>      aplus-beto.com.tw            211.23.229.58
>      www.aplus-beto.com.tw        211.23.229.58
>      mail.aplus-beto.com.tw       211.23.229.58
>      ftp.aplus-beto.com.tw        211.23.229.58
>which are check by TWNIC
>
>=================================================================
>At the first query, I can qery the full ns name (host.domain) of the
>domain
>
>Non-authoritative answer:
>aplus-beto.com.tw       MX preference = 10, mail exchanger =
>ibmserver.aplus-bet
>o.com.tw
>
>aplus-beto.com.tw       nameserver = ftp.aplus-beto.com.tw
>aplus-beto.com.tw       nameserver = www.aplus-beto.com.tw
>aplus-beto.com.tw       nameserver = mail.aplus-beto.com.tw
>aplus-beto.com.tw       nameserver = aplus-beto.com.tw
>ibmserver.aplus-beto.com.tw     internet address = 211.23.229.58
>www.aplus-beto.com.tw   internet address = 211.23.229.58
>aplus-beto.com.tw       internet address = 211.23.229.58
>==================================================================
>
>However, when I query the ns record, the result become that ns = host
>
>Non-authoritative answer:
>aplus-beto.com.tw       MX preference = 10, mail exchanger =
>ibmserver.aplus-bet
>o.com.tw
>aplus-beto.com.tw       nameserver = ibmserver
>
>aplus-beto.com.tw       nameserver = ibmserver
>
>==================================================================
>
>And I found out that is the zone setting which is stored at the dns
>server of aplus-beto.com.tw
>  
>
>>server aplus-beto.com.tw
>>    
>>
>Default Server:  aplus-beto.com.tw
>Address:  211.23.229.58
>  
>
>>set q=ns
>>aplus-beto.com.tw.
>>    
>>
>Server:  aplus-beto.com.tw
>Address:  211.23.229.58
>
>aplus-beto.com.tw       nameserver = ibmserver
>  
>
>=====================================================================
>Would any body tell me that it is correct ? When my name server query
>that result, my email server cannot send email to that domain.
>On the other hand, I use a older version of bind may be 8.1 to query
>the domain but result is always positive.
>Non-authoritative answer:
>aplus-beto.com.tw       nameserver = mail.aplus-beto.com.tw
>aplus-beto.com.tw       nameserver = aplus-beto.com.tw
>aplus-beto.com.tw       nameserver = ftp.aplus-beto.com.tw
>aplus-beto.com.tw       nameserver = www.aplus-beto.com.tw
>
>mail.aplus-beto.com.tw  internet address = 211.23.229.58
>aplus-beto.com.tw       internet address = 211.23.229.58
>ftp.aplus-beto.com.tw   internet address = 211.23.229.58
>www.aplus-beto.com.tw   internet address = 211.23.229.58
>
>Anybody can explain to me and any rfc to explain the formal setting of
>name server record ?
>
Your zone contains only 1 NS record, and it points to the bogus 
"ibmserver." name. By putting a period at the end of the name, you have 
designated that it is a *root*zone* name, but obviously no such name 
exists in the root zone. Either leave the period off that name, or 
fully-qualify it and *then* put a period on the end of it.

The NS records in your zone should match the delegations from the parent 
zone (in this case, the delegations from the com.tw nameservers). Since 
there are 4 nameservers in the delegation, I'm assuming you should have 
4 corresponding NS records in your zone, but of course they should be 
pointing to different IP addresses for redundancy/availability reasons. 
It's quite pointless for them all to refer to the same IP address. Where 
is the redundancy in that?

                                                                         
                                                - Kevin