A note on using name to IP / IP to name translations using DNS:

All answers you get from these translations depend on how the specific DNS domains are set up. Without going into details, when doing a name to IP translation and then doing a IP to name translation (a so called 'reverse lookup') you might end up with a different name than you started with. For instance for 'www.perlmonks.org' your scipt will output: 
209.197.123.153
66.39.54.27

[download]
When doing a reverse lookup on these addresses (I used the 'dig -x <addr>' to do this) you'll get: 
perlmonks.pair.com

[download]
and 
ads.perlmonks.org

[download]
This is because forward and reverse DNS don't have to be the same. And to complicate things even further DNS-records change in time. So an answer you got for a 'gethostbyname' query today can be different from an answer you got yesterday.

In reply to Re: Get server name from ip address by eXile
in thread Get server name from ip address by Anonymous Monk

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