Hi Hari and Jarek, it seems
FLUME-2547 removed SSLv2Hello from exclude list of Avro Sink by changing NettyAvroRpcClient.java, but it is not removed from "Avro Sink" part of Flume UG accordingly.
I opened JIRA
FLUME-2575 and uploaded a patch to fix the UG. Pls review if I understand it correctly, thanks !