A website and email can share a domain while running on different servers. Changing nameservers without carrying over the full configuration can disrupt messages, verification records and services that seemed unrelated to the move. DNS is the map to those destinations. Before changing it, obtain the current map and plan the transition period.
Inventory more than the homepage
Check the main domain, www, subdomains, email and external services. A and AAAA records point to addresses, CNAME can reference another name, MX matters for incoming mail, and TXT may contain authentication or verification information. Do not delete a TXT record simply because it is unfamiliar. Identify its service and owner before making changes.
Decide exactly what is moving
If only web hosting moves, changing the website destination may be enough. If nameservers change, prepare the complete zone at the new DNS provider. Confirm separately where mailboxes remain and who maintains SPF, DKIM and DMARC. Record old and approved new values so that recovery does not rely on memory.
Understand caching and TTL
TTL specifies how long a DNS answer may be cached. Lowering it in advance can shorten parts of the transition, but it does not remove every delay or retroactively clear cached answers. Do not promise an identical switch time for every visitor. Keep the old service available long enough for verification and requests that still reach it.
Check certificates and both destinations
The new server must answer for the correct hostname and have a suitable certificate. Test beforehand using an appropriate technical method without exposing credentials. After the move, check the website and email from more than one network. A successful result on the administrator’s computer may reflect different cached information from a customer’s device.
Finish only after verification
Test incoming and outgoing mail with authorised messages, plus forms and important pages. For dynamic websites, reconcile data that changed during the transition. Do not close the old account before checking copies and dependencies. If problems appear, use the recovery plan and communicate what is affected instead of repeatedly changing values at random.
Sources and further reading
A CloudCity editorial guide informed by the documentation below. Check the official source for rules and procedures that may change.
