Re: troubleshooting reverse DNS

["Jeremy C. Reed" <reed@wcug.wwu.edu>]

> For some reason the reverse (in-addr.arpa) mapping of an IP doesn't
> always work.
> 
> dig -x 209.102.25.210

... rest of examples clipped ...

Using dnstrace, it looks like a few of the nameservers I queried have a
poisoned or corrupted cache; e.g.:

 $ dnstrace -c 210.25.102.209.in-addr.arpa
 Tracing to 210.25.102.209.in-addr.arpa via 127.0.0.1, timeout 15 seconds
 127.0.0.1 (127.0.0.1) 
  |\___ ipdns2.hinet.net (168.95.1.14) 
   \___ ipdns1.hinet.net (168.95.192.14)

hinet.net -- a known spammer -- apparently is providing authoritative data
it isn't authoritative for.

  Jeremy C. Reed (who needs to get a newer cricket book)