Guide7 min readUpdated 7 Sept 2026

IONOS: use custom nameservers or add a Pages CNAME

Follow the current Domains & SSL paths for an IONOS root domain or Pages subdomain.

IONOS lets customers set custom nameservers for a root domain and create a CNAME for a subdomain. Use only the AlphaBlue-confirmed path.

Save current DNS records before changing nameservers. IONOS states that records configured in its DNS service are not active after external nameservers take over.

Provider instructions last verified: 7 September 2026, against current IONOS Help pages.

Path A: let AlphaBlue manage DNS

  1. Wait for AlphaBlue to confirm the replacement Cloudflare zone is ready.
  2. Sign in to IONOS and open Domains & SSL.
  3. Find the root domain.
  4. Select the gear icon under Actions.
  5. Select Name Server.
  6. Select Use Custom Name Servers.
  7. Enter the exact values supplied by AlphaBlue in Name Server 1 and Name Server 2.
  8. Do not invent values for optional additional nameservers.
  9. Select Save.
  10. Capture the saved nameserver screen and send it to AlphaBlue.

Do not use the subdomain NS-record editor for this root-domain change.

Path B: keep IONOS DNS and add a Pages CNAME

  1. Wait for the AlphaBlue Pages hostname and setting card.
  2. Open Domains & SSL.
  3. Select the gear icon for the desired subdomain or choose Manage Subdomains from the root domain.
  4. Beside the selected subdomain, select the gear icon → DNS.
  5. Check for an existing A, AAAA or CNAME using that hostname.
  6. If one exists, stop and send a screenshot.
  7. Select ADD RECORD → CNAME.
  8. Enter the exact subdomain label in Hostname.
  9. Enter the exact <project>.pages.dev hostname in Point to, without http:// or https://.
  10. Keep the default TTL unless instructed otherwise.
  11. Select Save and send AlphaBlue a screenshot.

IONOS advises using CNAME for a subdomain, not the root domain. That matches this course’s customer-managed DNS path.

Stop and contact AlphaBlue if

  • you are editing a subdomain NS record instead of root-domain nameservers;
  • IONOS shows the domain uses another DNS provider;
  • the selected subdomain already has an A, AAAA, CNAME or IONOS product binding;
  • the UI offers forwarding instead of DNS;
  • email or another service warning appears.

Official sources