The short answer.
Name servers indicate where to find your domain's DNS data; the records then connect its names to the expected services. TTL influences how long responses are kept in cache, but does not guarantee that all users will see a change at the same moment.
- Modifying a record and changing name servers are two different operations.
- A domain can use separate providers for the site, the DNS and email.
- Prepare all the necessary records before changing DNS management.
01What is the role of the domain and the DNS?
A domain is a name registered according to the rules of its extension. The DNS is the system that makes it possible to find data associated with this name, in particular addresses or email information. The hosting runs the site or application that responds to visitors.
These functions can be grouped together or split between several providers. Buying a domain does not automatically move a site, and changing hosting does not always require transferring its registration.
02What do name servers do?
Authoritative name servers respond with the data from the zone they manage. Domain delegation allows resolvers to find these servers. Your resolver is the service that performs DNS lookups to answer your device's requests.
Modifying a zone that is no longer used by delegation can leave users receiving the old information. Identify the active name servers and the zone manager.
03Which records should you recognize?
Each type serves a specific function. The values must come from the service you want to connect: do not copy an address or mail server found in an example. The main name and a subdomain such as www may require separate entries.
| Type | Usual role |
|---|---|
| A | Associates a name with an IPv4 address. |
| AAAA | Associates a name with an IPv6 address. |
| CNAME | Makes one name an alias of another name. |
| MX | Indicates the email receiving servers and their priority. |
| TXT | Publishes text, in particular for certain service verifications. |
| NS | Identifies the name servers of a zone or a delegation. |
04What is the TTL for?
TTL, expressed in seconds, indicates how long a DNS response is kept in cache. A response already cached can therefore continue to be used for its remaining duration. Changing the TTL at the time of the change does not retroactively erase all existing caches.
Querying different zones, local caches and delegation can occur at different stages. Avoid promises of universal propagation within minutes or at a fixed time. For a migration, prepare the schedule and verify the responses observed from several resolvers.
05Prepare changes without forgetting other services
Before changing name servers, export or note the necessary records and prepare the new zone. A site that works after the migration does not prove that email reception or third-party service validation also works.
Control subdomains, email entries, and TXT or CNAME verifications. If your domain uses DNSSEC, have that part of the migration coordinated as well. Do not remove a configuration that is still in use until the transition has been verified.
- The primary domain and the necessary subdomains are present.
- Email records have been preserved.
- Values match each service's instructions.
06Check the DNS then the service itself
Query the expected types and compare their responses with your configuration. Then test the site or application using the correct name, not just its IP address. The web server and its HTTPS certificate must also recognize this name for the connection to succeed correctly.
At WispHost, availability search is a first step in choosing your address. Nameservers, DNS records, and the conditions of the extension must be checked when putting it into service. For a migration, prepare the list of services to keep before changing the delegation.
Sources & references
To explore the technical points further and find the information at its source.