The following error occurred, causing the master node to crash. What is the reason for this?

[galenliu6]

2023-09-08T11:57:20,916 INFO [HttpClient-Netty-Worker-67] org.apache.druid.java.util.http.client.pool.ResourcePool - giveBack called after being closed. key[http://cbi-olap2:15283] 2023-09-08T11:57:20,917 ERROR [HttpClient-Netty-Worker-68] com.google.common.util.concurrent.ExecutionList - RuntimeException while executing runnable com.google.common.util.concurrent.Futures$4@a977809 with executor java.util.concurrent.ScheduledThreadPoolExecutor@15cc3f1f[Terminated, pool size = 0, active threads = 0, queued tasks = 0, completed tasks = 2924] java.util.concurrent.RejectedExecutionException: Task java.util.concurrent.ScheduledThreadPoolExecutor$ScheduledFutureTask@2a6a071b rejected from java.util.concurrent.ScheduledThreadPoolExecutor@15cc3f1f[Terminated, pool size = 0, active threads = 0, queued tasks = 0, completed tasks = 2924]