shell:$ nslookup -timeout=2 -retry=1 'corp.mobile.rakuten.co.jp'
Server:		75.98.161.224
Address:	75.98.161.224#53

Non-authoritative answer:
corp.mobile.rakuten.co.jp	canonical name = any3.mobile.rakuten.co.jp.edgekey.net.
any3.mobile.rakuten.co.jp.edgekey.net	canonical name = e242335.a.akamaiedge.net.
Name:	e242335.a.akamaiedge.net
Address: 23.62.106.168
Name:	e242335.a.akamaiedge.net
Address: 23.62.106.174