shell:$ nslookup -timeout=2 -retry=1 'a.ns.facebook.com'
Server:		75.98.161.224
Address:	75.98.161.224#53

Non-authoritative answer:
Name:	a.ns.facebook.com
Address: 129.134.30.12
Name:	a.ns.facebook.com
Address: 2a03:2880:f0fc:c:face:b00c:0:35