This limit can be set by changing the [search.max_open_scroll_context] setting

[2021-07-16T08:57:41,025][WARN ][r.suppressed             ] [CNHQ-20018523N] path: /.kibana_task_manager/_update_by_query, params: {ignore_unavailable=true, refresh=true, conflicts=proceed, index=.kibana_task_manager}
org.elasticsearch.action.search.SearchPhaseExecutionException: all shards failed
at org.elasticsearch.action.search.AbstractSearchAsyncAction.onPhaseFailure(AbstractSearchAsyncAction.java:661) [elasticsearch-7.13.3.jar:7.13.3]
at org.elasticsearch.action.search.AbstractSearchAsyncAction.executeNextPhase(AbstractSearchAsyncAction.java:384) [elasticsearch-7.13.3.jar:7.13.3]
at org.elasticsearch.action.search.AbstractSearchAsyncAction.onPhaseDone(AbstractSearchAsyncAction.java:694) [elasticsearch-7.13.3.jar:7.13.3]
at org.elasticsearch.action.search.AbstractSearchAsyncAction.onShardFailure(AbstractSearchAsyncAction.java:467) [elasticsearch-7.13.3.jar:7.13.3]
at org.elasticsearch.action.search.AbstractSearchAsyncAction.access$000(AbstractSearchAsyncAction.java:62) [elasticsearch-7.13.3.jar:7.13.3]
at org.elasticsearch.action.search.AbstractSearchAsyncAction$1.onFailure(AbstractSearchAsyncAction.java:316) [elasticsearch-7.13.3.jar:7.13.3]
at org.elasticsearch.action.ActionListener$Delegating.onFailure(ActionListener.java:66) [elasticsearch-7.13.3.jar:7.13.3]
at org.elasticsearch.action.ActionListenerResponseHandler.handleException(ActionListenerResponseHandler.java:48) [elasticsearch-7.13.3.jar:7.13.3]
at org.elasticsearch.action.search.SearchTransportService$ConnectionCountingHandler.handleException(SearchTransportService.java:400) [elasticsearch-7.13.3.jar:7.13.3]
at org.elasticsearch.transport.TransportService$5.handleException(TransportService.java:738) [elasticsearch-7.13.3.jar:7.13.3]
at org.elasticsearch.transport.TransportService$ContextRestoreResponseHandler.handleException(TransportService.java:1283) [elasticsearch-7.13.3.jar:7.13.3]
at org.elasticsearch.transport.TransportService$DirectResponseChannel.processException(TransportService.java:1392) [elasticsearch-7.13.3.jar:7.13.3]
at org.elasticsearch.transport.TransportService$DirectResponseChannel.sendResponse(TransportService.java:1366) [elasticsearch-7.13.3.jar:7.13.3]
at org.elasticsearch.transport.TaskTransportChannel.sendResponse(TaskTransportChannel.java:50) [elasticsearch-7.13.3.jar:7.13.3]
at org.elasticsearch.transport.TransportChannel.sendErrorResponse(TransportChannel.java:45) [elasticsearch-7.13.3.jar:7.13.3]
at org.elasticsearch.action.support.ChannelActionListener.onFailure(ChannelActionListener.java:40) [elasticsearch-7.13.3.jar:7.13.3]
at org.elasticsearch.action.ActionRunnable.onFailure(ActionRunnable.java:77) [elasticsearch-7.13.3.jar:7.13.3]
at org.elasticsearch.common.util.concurrent.ThreadContext$ContextPreservingAbstractRunnable.onFailure(ThreadContext.java:720) [elasticsearch-7.13.3.jar:7.13.3]
at org.elasticsearch.common.util.concurrent.AbstractRunnable.run(AbstractRunnable.java:28) [elasticsearch-7.13.3.jar:7.13.3]
at java.util.concurrent.ThreadPoolExecutor.runWorker(ThreadPoolExecutor.java:1142) [?:1.8.0_131]
at java.util.concurrent.ThreadPoolExecutor$Worker.run(ThreadPoolExecutor.java:617) [?:1.8.0_131]
at java.lang.Thread.run(Thread.java:748) [?:1.8.0_131]
Caused by: org.elasticsearch.ElasticsearchException: Trying to create too many scroll contexts. Must be less than or equal to: [500]. This limit can be set by changing the [search.max_open_scroll_context] setting.
at org.elasticsearch.search.SearchService.createAndPutReaderContext(SearchService.java:676) ~[elasticsearch-7.13.3.jar:7.13.3]
at org.elasticsearch.search.SearchService.createOrGetReaderContext(SearchService.java:661) ~[elasticsearch-7.13.3.jar:7.13.3]
at org.elasticsearch.search.SearchService.executeQueryPhase(SearchService.java:434) ~[elasticsearch-7.13.3.jar:7.13.3]
at org.elasticsearch.search.SearchService.lambda$executeQueryPhase$2(SearchService.java:411) ~[elasticsearch-7.13.3.jar:7.13.3]
at org.elasticsearch.action.ActionRunnable.lambda$supply$0(ActionRunnable.java:47) ~[elasticsearch-7.13.3.jar:7.13.3]
at org.elasticsearch.action.ActionRunnable$2.doRun(ActionRunnable.java:62) ~[elasticsearch-7.13.3.jar:7.13.3]
at org.elasticsearch.common.util.concurrent.ThreadContext$ContextPreservingAbstractRunnable.doRun(ThreadContext.java:732) ~[elasticsearch-7.13.3.jar:7.13.3]
at org.elasticsearch.common.util.concurrent.AbstractRunnable.run(AbstractRunnable.java:26) ~[elasticsearch-7.13.3.jar:7.13.3] 

Solution:
http://localhost:9200/_cluster/settings
Set the value of the variable: search.max_open_scroll_context

{

"persistent": {

    "search.max_open_scroll_context": 5000

},

"transient": {

    "search.max_open_scroll_context": 5000

}

}

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