I spent close to two days and tracked down the solution to a major issue with Avro / GenericRecord and Flink. In short, there is a field marked 'transient' in Avro 1.7.6 and earlier which interferes with correct Kryo serialization. This was fixed in Avro 1.7.7, but Flink is dependent on Avro 1.7.6 in its POM.xml file.
I recorded the root cause and solution in JIRA https://issues.apache.org/jira/browse/FLINK-5039 However the issue is marked as 'minor' I'd like a little more attention and hopefully the Avro version can be updated for Flink 1.1.4? In the meantime, I have created a custom Flink distribution Jar containing the Avro 1.7.7 classfiles and it is working perfectly for me now. Best Regards, Dave Torok
