mail-en05-crm-ms01.avature.net.
Question and response
Question
dig 131.128-255.56.217.74.in-addr.arpa. PTR
Answer
131.128-255.56.217.74.in-addr.arpa. 360 PTR mail-en05-crm-ms01.avature.net.
Authority
128-255.56.217.74.in-addr.arpa. 172800 NS ns-1468.awsdns-55.org.
128-255.56.217.74.in-addr.arpa. 172800 NS ns-1872.awsdns-42.co.uk.
128-255.56.217.74.in-addr.arpa. 172800 NS ns-250.awsdns-31.com.
128-255.56.217.74.in-addr.arpa. 172800 NS ns-707.awsdns-24.net.
Additional
. 0 OPT ; payload 4096, xrcode 0, version 0, flags 0