mx-cluster-ca01.hornetsecurity.com.
Question and response
Question
dig 231.224-255.133.163.108.in-addr.arpa. PTR
Answer
231.224-255.133.163.108.in-addr.arpa. 3600 PTR mx-cluster-ca01.hornetsecurity.com.
Authority
The response has no authority records.
Additional
. 0 OPT ; payload 1232, xrcode 0, version 0, flags 0