Sorry, you can't have a CNAME on the root domain - Porkbun refuses CNAME for Zeabur apex domain

TL;DR

Switched the record type to ALIAS like Porkbun suggested, but the root domain still would not resolve properly while subdomains worked fine. Porkbun's ALIAS record is the equivalent for apex domains, but you need to make sure it actually resolves to the right target.

Steps

1. Tried pointing my root domain at Zeabur in Porkbun and got refused with an error saying a CNAME on the root domain violates RFC and will break things. Switched the record type to ALIAS like Porkbun suggested, but the root domain still would not resolve properly while subdomains worked fine. The maintainer pointed out that apex CNAMEs are not allowed by DNS rules and suggested flattening the CNAME by digging the A records of Zeabur's target and putting those A records on the apex directly.
2. You cannot put a CNAME on an apex/root domain, that is an actual RFC restriction, not a Porkbun quirk. Porkbun's ALIAS record is the equivalent for apex domains, but you need to make sure it actually resolves to the right target. The maintainer suggested flattening the CNAME yourself: run dig against Zeabur's CNAME target to get its A records, then put those A records directly on your root domain. One more thing from the thread: in the end the reporter's issue turned out to be plain Porkbun DNS propagation delay, so if you just changed records, wait a bit and recheck before assuming something is broken.

When to use

You are seeing this: Tried pointing my root domain at Zeabur in Porkbun and got refused with an error saying a CNAME on the root domain violates RFC and will break things. Use this skill when you run into "Sorry, you can't have a CNAME on the root domain - Porkbun refuses CNAME for Zeabur apex domain".

When not to use

If your error message or symptom does not match what is described above, this is probably not your fix. Search for your exact error text instead of forcing this one to fit.

Versions

No specific versions are mentioned in the source material, so treat the fix as generally applicable and check the examples against whatever you have installed.

Why this happens

The original report does not dig into a root cause. It documents the symptom and the fix that resolved it.

Asked in the thread (https://vectle.com/threads/thrpP14lg8kZqHPB9Ky8-bMw): Tried pointing my root domain at Zeabur in Porkbun and got refused with an error saying a CNAME on the root domain violates RFC and will break things. Switched the record type to ALIAS like Porkbun suggested, but the root domain still would not resolve properly while subdomains worked fine. The maintainer pointed out that apex CNAMEs are not allowed by DNS rules and suggested flattening the CNAME by digging the A records of Zeabur's target and putting those A records on the apex directly. The verified answer: You cannot put a CNAME on an apex/root domain, that is an actual RFC restriction, not a Porkbun quirk. Porkbun's ALIAS record is the equivalent for apex domains, but you need to make sure it actually resolves to the right target. The maintainer suggested flattening the CNAME yourself: run dig against Zeabur's CNAME target to get its A records, then put those A records directly on your root domain. One more thing from the thread: in the end the reporter's issue turned out to be plain Porkbun DNS propagation delay, so if you just changed records, wait a bit and recheck before assuming something is broken. Source: https://github.com/zeabur/zeabur/issues/527 Thread: https://vectle.com/threads/thrpP14lg8kZqHPB9Ky8-bMw