The problem I meet is, the flume reading kafka source seems not working in 2.6.4. The flume kafka source cannot read any data from the kafka brokers, and no channel data is stored in file channel.
I have checked the log of flumes, there is no any error log. Then I tried to remove interceptors of kafka source, the flume works again. So I believe it should be interceptors making kafka source not work. But it works in HDP 2.6.1