The Certification Authority Authorization (CAA) DNS Resource Record allows a DNS domain name holder to specify one or more Certification Authorities (CAs) authorized to issue certificates for that domain.
How to check a domain’s CAA record which is identified by a type257 DNS record:
$ dig +short -t TYPE257 google.com
\# 19 0005697373756573796D616E7465632E636F6D
For more information: