DNS look up , example of Non-Blocking function of JS .

gistfile1.js

var SiteArray = ['google.com','webonise.com','facebook.com','techcrunch.com','indiatimes.com'];

var dns = require('dns');

for(var i = 0 ; i < SiteArray.length ; i++){
	dns.lookup(SiteArray[i],function(err,ip){
		if (err) return handleError(err);
		console.log( " %s resolved to %s ", SiteArray[i],ip );
	});
}

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