shell:$ nslookup -timeout=2 -retry=1 'rtb.channelexco.com'
Server:		127.0.0.53
Address:	127.0.0.53#53

Non-authoritative answer:
rtb.channelexco.com	canonical name = p-lb.cdtx.co.
Name:	p-lb.cdtx.co
Address: 23.81.164.159