Migrate domains

Use this as a reference, not a required sequence. Adapt the approach and code to suit the app and the user’s needs.

Separate the changes#

Moving to Render does not require moving the registrar or DNS provider. Record existing records and choose a canonical URL first.

Connect the domain#

Deploy and test the onrender.com URL. In the Render service's Settings → Custom Domains, add the domain, then follow its exact DNS instructions and verify it. Render provisions TLS. If CAA records exist, allow Render’s documented certificate authorities. With a Cloudflare-proxied hostname, use Full (strict) TLS.

Configure both apex and www intentionally. For a subdomain, use the CNAME target Render displays; for an apex, follow its provider-specific instructions instead of guessing an IP. Preserve MX, TXT, verification, and unrelated subdomain records. Update OAuth callbacks and links to the canonical URL.

For a static site, add redirects in its Redirects/Rewrites settings. An SPA rewrite such as /* → /index.html is not a canonical-host redirect. For a web service, handle application redirects in the server while preserving paths and query strings.

Verify and retire old routes#

Test HTTPS, apex/www, nested paths, queries, redirects, and email delivery. If using an access gateway, verify the application rejects requests without the gateway’s valid JWT; disabling the default hostname alone is insufficient.

Stop old writes/jobs and sync final data before switching traffic. To redirect val.run URLs, add redirects once the migrated app is verified. Transfer registration only if requested and track it separately.

Keep prior DNS settings and backups. Rolling back after new data is written requires reconciliation.