Fail to lookup virutal domain name.

Kevin Darcy kcd at daimlerchrysler.com
Wed Sep 13 00:49:01 UTC 2000


PTR's are a special case for named: they are never "cycled" or
"randomized", but always given out in "fixed" order. mishi.bidbid.com is
the first PTR with the name 1.1.16.172.in-addr.arpa in your zonefile, so
it's always given as the first record in the answer. If you want to see
the *other* PTR records in the answer, with nslookup you need to turn on
"debug". Or just use "dig".

If you want one of the other PTR's to show up first, then rearrange their
order in the zonefile.

Then again, except for DNS query tools, nothing really knows or cares
about the other answers in the response beyond the first, so why even
bother having those extra PTR's?

Even better, why even bother having 4 A records? Make 3 of them aliases.
Then if you ever want to change the underlying IP address, you only have 1
record to change.


- Kevin

Sam Wun wrote:

> HI,
>
> I have 3 domain names in my server, fastline.bidbid.com,
> mishi.bidbid.com
> and www.sam.com, where www.sam.com is a virtual host.
> fastline.bidbid.com
> is pointing at 192.168.1.1, mishi.bidbid.com is pointing at
> 172.16.1.1, and www.sam.com also pointing at 172.16.1.1,  thus:
>
> fastline.bidbid.com -> 192.168.1.1
> mishi.bidbid.com -> 172.16.1.1
> www.sam.com -> 172.16.1.1
>
> when I do nslookup on the www.sam.com ( the virtural name), it shows:
>
> swun at fastline ~ > nslookup www.sam.com
> Server:  fastline.bidbid.com
> Address:  192.168.1.1
>
> Name:    www.sam.com
> Address:  172.16.1.1
>
> But the following may not be right?
>
> swun at fastline ~ > nslookup 172.16.1.1
> Server:  fastline.bidbid.com
> Address:  192.168.1.1
>
> Name:    mishi.bidbid.com
> Address:  172.16.1.1
>
> I would expect nslookup 172.16.1.1 should show me the Name www.sam.com
> as
> well?
> What may be wrong with my setting then?
>
> Here is my db.sam zone file:
> swun at fastline /etc/namedb > cat db.sam
> $TTL 432000
> @ IN  SOA sam.sam.com. root.sam.sam.com. ( 2000090700 10800 3600 604800
> 86400 )
>   IN  NS  sam.sam.com.
>
> localhost            IN  A     127.0.0.1
> sam                  IN  A     172.16.1.1
> sam                  IN  MX    10 sam.sam.com.
>
> www.sam.com.         IN  A     172.16.1.1
>
> And my db.172.16.1.1 file:
> swun at fastline /etc/namedb > cat db.172.16.1
> $TTL 432000
> @ IN  SOA fastline.bidbid.com. root.fastline.bidbid.com. ( 2000090700
> 10800
> 3600 604800 86400 )
>   IN  NS  fastline.bidbid.com.
>   IN  NS  mishi.bidbid.com.
>
> 1.1.16.172.IN-ADDR.ARPA.        IN  PTR   mishi.bidbid.com.
> 200.1.16.172.IN-ADDR.ARPA.      IN  PTR   db.bidbid.com.
>
> 1.1.16.172.IN-ADDR.ARPA.        IN  PTR   www.sam.com.
> 1.1.16.172.IN-ADDR.ARPA.        IN  PTR   www.rolandx.com.
> 1.1.16.172.IN-ADDR.ARPA.        IN  PTR   www.fineworkx.com.
>
> Thanks
> Sam






More information about the bind-users mailing list