Question and response
Question
dig u21890913.wl164.sendgrid.net. PTR
Answer
The response has no answer records.
Authority
wl164.sendgrid.net. 1800 SOA aisha.ns.cloudflare.com. dns.cloudflare.com. 2397430065 10000 2400 604800 1800
Additional
. 0 OPT ; payload 1232, xrcode 0, version 0, flags 0