Not that this has anything to do with Perl really. But anyway, what can you do:

  1. A hostname A can give you an IP-number if it resolves.
  2. A reverse lookup of the IP-number may give you a hostname B if it resolves.
  3. A and B may or may not be the same.

You should think of hostnames as nothing other than a "roadmap" to get to a specific (IP) address. And there are an infinite number of ways to Rome: some of them are described (have a hostname) and some are not described. But you will never be able to find them all, unless someone (else) tells them to you.

Hope this helps.

Liz

In reply to Re: Finding hostname aliases by liz
in thread Finding hostname aliases by marknm

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