Submit supervisor spec, one task SUCCESS, the others never Handoff

Hi all,
Our Kafka indexing service is very weird. We have a datasource with 10 replicas. Sometimes when submitting the new supervisor, it took a rather longer time than usual. As it finally finished submitting, it should new 10 running tasks and graceful shutdown the exiting supervisor. But there were no new tasks, and one of the old tasks finished with status SUCCESS, and the others were running. When the taskDuration elapsed, the others 9 tasks never Handoff.

The druid used is 0.9.2-rc2. We have a lot of datasource, and it seems the problem randomly pick datasources.

Some supervisor spec is as follows:

"replicas":10,
"taskCount":1,
"taskDuration":"PT1H",
"lateMessageRejectionPeriod":"PT48H",
"completionTimeout":"PT24H",
"buildV9Directly":true

Thank you very much,

Xinxin

Can you post your overlord logs? Also, does stopping and restarting the overlord fix things?