After the switch, check more than one A record

IPv6, aliases and email can still point to the old environment.

Review both A and AAAA

Changing A while keeping an old AAAA can send some clients to the previous server. Whether IPv6 is required and which address to use should come from the target platform’s actual configuration.

Check service entry points

A www, API or asset hostname may still use the old CNAME target. Query against your migration checklist. With a proxy or CDN, distinguish its public addresses from the origin server; public answers do not necessarily reveal the origin directly.

Separate DNS review from acceptance testing

Once DNS answers match your expectations, verify HTTPS, website features and email flow too. This tool provides DNS results only. It does not confirm that the new application, content or database migration is complete.

This guide explains public DNS responses. Before changing production settings, check the documentation for your current domain and hosting providers.