Sync/Blocking DNS resolve. Main usecase is in node server startup.
var dnsSync = require('dns-sync');
console.log(dnsSync.resolve('www.paypal.com'));     //should return the IP address
console.log(dnsSync.resolve('www.yahoo.com'));
console.log(dnsSync.resolve('www.non-host.something')); //should return null
console.log(dnsSync.resolve('www.google.com', 'AAAA')); //should return AAAA records
console.log(dnsSync.resolve('google.com', 'NS'));   //should return NS record