Unable to find any PTR-records for the specified domain/ip :(
Log
+000
Resolving PTR record of '172.99.250.0'
+291
ERRNo PTR record availible DNS server 'ns-386.awsdns-48.com' raised an NotExistentDomain error, while beeing queried for PTR-records on domain '0.250.99.172.in-addr.arpa'.