I have seen that when you are working with ipv6, you can find this error. Because they use a split of ipv4,
String[] parts = address.getHostAddress().split("\\.");
String reverseIP = parts[3] + "." + parts[2] + "." + parts[1] + "."
+ parts[0] + ".in-addr.arpa";
I have found a posible solution. Put this in the hadoop-env.cmd, but i cant test yet.
-Djava.net.preferIPv4Stack=true