I have installed logstash log4j filter plugin.When i check logstash Configtest ,i have the following Warning
log4j:WARN No appenders could be found for logger (org.apache.http.impl.conn.PoolingHttpClientConnectionManager).
log4j:WARN Please initialize the log4j system properly.
log4j:WARN See http://logging.apache.org/log4j/1.2/faq.html#noconfig for more info.