What could cause Coordinator instance to stop being a Leader?

Hi, All.

I am currently face a puzzling situation where in my current Druid configuration only one instance of Coordinator is allocated.
At one point, it is temporarily stop being the Leader. I wonder what could be the possible cause of that?

I am currently running Druid 0.16.0.

Hi Keyne,
Can you give more details about your cluster(how many master nodes, query nodes ,data nodes)?

Any clues(errors/warnings/failures/exceptions) from your coordinator logs?

Thank you,


Hi Siva,

Currently, this is the configuration for the Druid cluster:

  • Coordinator: 1 instance
  • Overlord: 1 instance
  • Broker: 1 instance
  • Historical: 4 instances

They are running on ECS and so far I only get the docker log which did not goes as far to the point when the issue arises.
I failed to locate the actual logs within the running docker container itself, maybe if you can show some light on which folder I should look or which configuration I should update?

Thank you very much in advance.

Load balancer

U.S. BANCORP made the following annotations---------------------------------------------------------------------

Hi keene,
Generally logs are created in var/sv// under druid home directory . For example, coordinator log should be at var/sv/coordinator/ under druid home directory.


Try to run find command to search for filename “current” and see whether you will be able to locate log files created by druid.