Elasticsearch - Attempted to send a bulk request to elasticsearch' but Elasticsearch appears to be unreachable or down!

Hi Team,

We are using the ELK stack and we are getting the below error in our logstash pods logs .
Logs are sending slowly or some time it is not at all processing the logs .

Note: We checked the elasatic search service local host and it is up and running all the time though the error was captured.

Version we used in our platform:
Elasticsearch - Elasticsearch:7.4.2
Logstash - logstash:6.8.22
kibana - kibana:7.4.2

Elasticsearch-cluster-data 17 nodes
Elasticsearch-cluster-master 3 nodes

Error Message in logstash:
[ERROR] 2022-01-12 14:49:02.747 [[main]>worker0] Elasticsearch - Attempted to send a bulk request to Elasticsearch' but Elasticsearch appears to be unreachable or down! {:error_message=>"Elasticsearch Unreachable: [http://es.elastic:9200/][Manticore::SocketTimeout] Read timed out", :class=>"LogStash::Outputs::Elasticsearch::HttpClient::Pool::HostUnreachableError", :will_retry_in_seconds=>8}

[WARN ] 2022-01-12 14:49:05.562 [Ruby-0-Thread-4: /usr/share/logstash/vendor/bundle/jruby/2.5.0/gems/logstash-output-Elasticsearch-9.4.0-java/lib/logstash/outputs/Elasticsearch/http_client/pool.rb:232] Elasticsearch - Restored connection to ES instance {:url=>"http://es.elastic:9200/"