Look at Net::DNS as that should have less overhead than using system or backticks, but keep in mind that your problem (at least as phrased) is unsolvable.

There is one and only one PTR record for a given IP; there can be an unlimited number of A records which all resolve to the same IP (not to mention CNAME aliases). There's no way to get anything other than the PTR address from DNS. If you've got a list of hostnames you could build a mapping on your own, but it's only going to be complete as your list of hostnames.

In reply to Re: Retrieving all hostnames for an IP address... by Fletch
in thread Retrieving all hostnames for an IP address... by RMaxwell

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