Error connecting to node kafka-broker:9092 (id: 1 rack: null) java.net.UnknownHostException: kafka-broker

When I use kafka plugin in logstash, I am getting the below error.

[2023-03-10T15:11:46,310][WARN ][org.apache.kafka.clients.NetworkClient][main][289f84d5c44d64af9505535a5352178af25a608c83252a1c520ab39a4faa4855] [Consumer clientId=logstash-0, groupId=logstash] Error connecting to node kafka-broker:9092 (id: 1 rack: null)
java.net.UnknownHostException: kafka-broker

Yaml file :
input {
kafka {
bootstrap_servers => "localhost:9092"
topics => ["topicdemo"]
auto_offset_reset => "earliest"
decorate_events => true
}
}
filter {

	}

output {
elasticsearch {
hosts => ["https://localhost:9200"]
cacert => 'C:\logstash-8.6.2-windows-x86_64\logstash-8.6.2\config\http-cert\ca.crt'
index => "topicdemo"
user => "elastic"
password => "********"
}
}