shell:$ nslookup -timeout=2 -retry=1 'topup-flow.firebaseapp.com' Server: 1.1.1.1 Address: 1.1.1.1#53 Non-authoritative answer: Name: topup-flow.firebaseapp.com Address: 199.36.158.100 Name: topup-flow.firebaseapp.com Address: 2620:0:890::100