我有一个docker logstash配置如下：

input {
  tcp {
    port => 5000
  }
}

output {
  elasticsearch {
    hosts => ["https://my-custom-elastic.com:9321"]

字符串
预期：
我希望logstash连接到https://my-custom-elastic.com:9321，而不是http：//elasticsearch：9200/
实际：
在100%的情况下，我得到了这个错误：

[2023-08-18T06:11:35,099][INFO ][logstash.licensechecker.licensereader] Elasticsearch pool URLs updated {:changes=>{:removed=>[], :added=>[http://elasticsearch:9200/]}}
[2023-08-18T06:11:35,409][INFO ][logstash.licensechecker.licensereader] Failed to perform request {:message=>"elasticsearch: Name or service not known", :exception=>Manticore::ResolutionFailure, :cause=>java.net.UnknownHostException: elasticsearch: Name or service not known}
[2023-08-18T06:11:35,415][WARN ][logstash.licensechecker.licensereader] Attempted to resurrect connection to dead ES instance, but got an error {:url=>"http://elasticsearch:9200/", :exception=>LogStash::Outputs::ElasticSearch::HttpClient::Pool::HostUnreachableError, :message=>"Elasticsearch Unreachable: [http://elasticsearch:9200/][Manticore::ResolutionFailure] elasticsearch: Name or service not known"}
[2023-08-18T06:11:35,599][INFO ][logstash.licensechecker.licensereader] Failed to perform request {:message=>"elasticsearch", :exception=>Manticore::ResolutionFailure, :cause=>java.net.UnknownHostException: elasticsearch}

型
我确信logstash正在获取正确的配置，因为在这个错误之后，几行之后，它确实连接到了我预期的目的地。
问：
为什么即使我配置了自定义主机，logstash仍然试图连接到localhost？