Unable to find any PTR-records for the specified domain/ip :(
Log
+000
Resolving PTR record of '172.86.224.0'
+111
ERRNo PTR record availible DNS server 'y.arin.net' raised an NotExistentDomain error, while beeing queried for PTR-records on domain '0.224.86.172.in-addr.arpa'.