What is DNS, and how does it connect a domain to a hosted application?

What is DNS, and how does it connect a domain to a hosted application?

DNS, the Domain Name System, helps clients find services using names. For a website, DNS resolution supplies information that lets a browser reach the hosting infrastructure. The hosting platform then uses the requested hostname to serve the intended application.

Follow the journey from name to application

When someone opens a wedding-planning domain, their device asks a resolver for the relevant DNS information. The resolver may answer from its cache or obtain information from the authoritative DNS system. Records describe addresses or aliases for the requested name.

An A record supplies an IPv4 address, while a CNAME makes one name an alias of another. These are different instructions. DNS does not contain the application's pages or decide which wedding dashboard a signed-in user may access. Vercel's DNS explanation describes this resolution process.

Configure both sides of the connection

Adding a DNS record is one part of connecting a custom domain. The hosting project must also recognize that domain and associate it with the correct deployment. Otherwise, reaching the provider's infrastructure may still produce an error or the wrong destination.

Use the actual record values supplied for the project. Identify the authoritative DNS provider before editing records; the company that sold the domain is not always the company serving its DNS.

Verify the layers separately

Check that DNS returns the intended information, that the hosting platform recognizes the hostname, and that HTTPS succeeds. Then test an application route such as an RSVP page.

If the homepage loads but login fails, the remaining problem may involve application configuration rather than DNS. Separating name resolution, hosting routing, transport security, and application behavior makes troubleshooting more precise and prevents unrelated changes from obscuring the original issue.