shell:$ nslookup -timeout=2 -retry=1 'fbcdn-b-a.akamaihd.com'
Server:		127.0.0.53
Address:	127.0.0.53#53

Non-authoritative answer:
fbcdn-b-a.akamaihd.com	canonical name = akamaihd.com.edgesuite.net.
akamaihd.com.edgesuite.net	canonical name = a1531.g.akamai.net.
Name:	a1531.g.akamai.net
Address: 23.223.17.138
Name:	a1531.g.akamai.net
Address: 23.223.17.133