Error reported by Druid's Zookeeper Client

Hi Druid,

I cannot restart a Druid historical node due to an issue of Druid’s Zookeeper Client. It complains the Packet len6343263 is too small. By searching on StackOverflow, I added the “-Djute.maxbuffer=50111000” to Druid’s bootstrap script and fix the issue temporarily. However, the root cause hasn’t been found out yet. Why does “Packet len” overflow and in what scenario the “Packet len” might be the bottleneck of Druid? What’s the goal of using Zookeeper by Druid? Looking forward to your reply!

The error message below:

2020-01-24T19:32:35,083 WARN [main-SendThread(audience-analytics-druid-zk-production.us-west-2.bds.aws:2181)] org.apache.zookeeper.ClientCnxn - Session 0x1024f262f2a0004 for server audience-analytics-druid-zk-production.us-west-2.bds.aws/10.65.66.48:2181, unexpected error, closing socket connection and attempting reconnect

java.io.IOException: Packet len6343263 is out of range!

at org.apache.zookeeper.ClientCnxnSocket.readLength(ClientCnxnSocket.java:113) ~[zookeeper-3.4.14.jar:3.4.14-4c25d480e66aadd371de8bd2fd8da255ac140bcf]

at org.apache.zookeeper.ClientCnxnSocketNIO.doIO(ClientCnxnSocketNIO.java:79) ~[zookeeper-3.4.14.jar:3.4.14-4c25d480e66aadd371de8bd2fd8da255ac140bcf]

at org.apache.zookeeper.ClientCnxnSocketNIO.doTransport(ClientCnxnSocketNIO.java:366) ~[zookeeper-3.4.14.jar:3.4.14-4c25d480e66aadd371de8bd2fd8da255ac140bcf]

at org.apache.zookeeper.ClientCnxn$SendThread.run(ClientCnxn.java:1141) [zookeeper-3.4.14.jar:3.4.14-4c25d480e66aadd371de8bd2fd8da255ac140bcf]