looking up rr.com associated ptr and a records (problem?)

Andrew Brown atatat at atatdot.net
Sun Sep 30 20:53:17 UTC 2001


>>>But it's not actually as bad as it looks -- they just have different
>>>names for the same hosts (and one missing one in this case):
>>>
>>>	$ host -a nycdns1.nyc.rr.com
>>>	nycdns1.nyc.rr.com      A       24.29.99.32
>>>	$ host -a nycdns1fa.rdc-nyc.rr.com
>>>	nycdns1fa.rdc-nyc.rr.com        A       24.29.99.32
>>>
>>>	$ host -a nycdns2.nyc.rr.com
>>>	nycdns2.nyc.rr.com      A       24.29.99.34
>>>	$ host -a nycdns2fa.rdc-nyc.rr.com
>>>	nycdns2fa.rdc-nyc.rr.com        A       24.29.99.34
>>
>>  i noted that.  i thought it looked like a dropped project to cut over
>>  dns server names.
>
>	The DNS delegates by name, not by IP address.  If the IP address 
>changes, that doesn't change the delegation.  If the names mis-match, 
>then that's messed up delegation information.

i meant "dropped" meaning the the upper set had been changed but not
the lower set.  or vice versa.  who knows?

>>>They do have some semi-serious problems with reverse is-matches for the
>>>NS hostnames:
>>>
>>>$ host -A nycdns1.nyc.rr.com
>>>  !!! nycdns1.nyc.rr.com address 24.29.99.32 maps to nycdns1fa.rdc-nyc.rr.com
>>>
>>>$ host -A nycdns2.nyc.rr.com
>>>  !!! nycdns2.nyc.rr.com address 24.29.99.34 maps to nycdns2fa.rdc-nyc.rr.com
>>>
>>>but it's not even serious enough to trip the TCP Wrappers "paranoid" check.
>>
>>  right.  my named, on the other hand, doesn't like it for some reason.
>
>	See above.  If you're going to be running nameservers, then their 
>reverse DNS should match.  Above all other machines on the Internet, 
>the reverse DNS for nameservers should match.

um...the requirement for a valid a record i can see, but dns doesn't
rely on names mapping back to addresses, does it?  or are you
referring only to human debugging capabilities and needs?

-- 
|-----< "CODE WARRIOR" >-----|
codewarrior at daemon.org             * "ah!  i see you have the internet
twofsonet at graffiti.com (Andrew Brown)                that goes *ping*!"
andrew at crossbar.com       * "information is power -- share the wealth."


More information about the bind-workers mailing list