I have this on sender side (log4j.properties file for jboss):
log4j.appender.LOGSTASH=org.apache.log4j.net.SocketAppender
log4j.appender.LOGSTASH.layout=org.apache.log4j.PatternLayout
log4j.appender.LOGSTASH.layout.ConversionPattern=%-5p %t %d{ISO8601} %l - %m%n
log4j.appender.LOGSTASH.RemoteHost=my.server.com
log4j.appender.LOGSTASH.ReconnectionDelay=60000
log4j.appender.LOGSTASH.Threshold=DEBUG
But on receiving side I always receive some default message, ConversionPattern doesnt work, even I remove everything and put just a text there. I have four jboss instances, so it is critical to me to define on every sender side some specific text, e.g. log4j.appender.LOGSTASH.layout.ConversionPattern=server1 %-5p %t %d{ISO8601} %l - %m%n