spf-d.mail.163.com has no CNAME records.
Question and response
Question
dig spf-d.mail.163.com. NS
Answer
The response has no answer records.
Authority
163.com. 60 SOA ns4.nease.net. admin.nease.net. 20292323 7200 1800 1209600 60
Additional
. 0 OPT ; payload 1232, xrcode 0, version 0, flags 0