shell:$ nslookup -timeout=2 -retry=1 'sentinel.airtel.africa'
Server:		127.0.0.53
Address:	127.0.0.53#53

Non-authoritative answer:
sentinel.airtel.africa	canonical name = irsojup.ng.impervadns.net.
Name:	irsojup.ng.impervadns.net
Address: 45.60.135.92