Note that CNAME flattening returns the target IP address, instead of the hostname. So if the target hostname cannot be resolved, there’s nothing for Cloudflare to return in DNS Only mode.
Not yet resolved,Thank you very much for your reply! The cname full host name resolved by nodelayer.net: 99ad7b74.netnode.cc, 99ad7b74.netnode.cc is resolved normally and returns ip:47.76.86.30, but nodelayer.net Domain zone apex CNAME flattening DNS Only resolution failed!