Reverse address entries

[Sam Wilson]

In article <mailman.807.1373643569.20661.bind-users at lists.isc.org>,
 "Novosielski, Ryan" <novosirj at ca.rutgers.edu> wrote:

> Came across another instance where [reverse lookups] may matter: TCP Wrappers.
> Although the case there was a bit more peculiar -- rr.net does not
> appear to have FORWARD DNS for at least some of its dynamic address
> space. So you can get a PTR, and then address validation fails on the
> forward address. I guess perhaps if you had no PTR it would never go
> that far.

Yep, when you have PTRs they should agree with the A records or paranoid 
reverse lookup will fail.  That should still be fairly quick, though, 
since there should be NXDOMAIN responses to the forward lookups rather 
than timeouts.

Sam

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