hi everyone,

sorry if i post on the wrong forum, but can't find any thread on log4j specifically.
i faced with a rather weird outcome of log4j. first of all to load preface information,
i'm using apache2.2 and load balanced 2 tomcat version 6 called tomcat1 & tomcat2 respectively. i made the tomcat1 & 2
point to a single webapp directory.

rough diagram looks like this:

     Apache2.2
         |
     ---------
     | |
  tomcat1 tomcat2
    | |
    -------------
          |
       webapps

as depicted above, any request send from apache to tomcat1 and
tomcat2 will use the same copy of servlet within the webapps/WEB-INF/classes dir. i set the log file to eg. "/log/mylog.log". the log4j settings is as below.

--------------------------------
<p>
log4j.rootLogger =DEBUG,DAILY
log4j.appender.DAILY=org.apache.log4j.DailyRolling FileAppender
log4j.appender.DAILY.layout=org.apache.log4j.Patte rnLayout
log4j.appender.DAILY.File=/log/mylog.log
log4j.appender.DAILY.Append=true

log4j.appender.DAILY.DatePattern='.'yyyy-MM-dd-HH
log4j.appender.DAILY.layout.ConversionPattern=%d %-5p [%t] %-17c{2} %3x - %m%n
</p>

based on the setting above, it should log every top hour
per file.

There are 2 problems i'm facing now:
1.
It logs every hour as expected. But the name of the file
where hour indicated differently than the contents being log.
   eg. filename is "mylog.log.2008-04-20-13" indicate 1pm.
       but the contents inside logs 2pm onwards.

2.
Log4j normally rollover and copy a new past hour to a new file. Leaving the default mylog.log as the current logging data before rollover and copy to another file (that is, currently logging 2pm onwards). But i saw it
logging both files at the same time in "mylog.log" and "mylog.log.2008-04-20-13". The file "mylog.log" logging 2pm onwards which is correct but it still log 2pm onwards /append the same information to "mylog.log.2008-04-20-13".

i suspect it might be something to do with concurrency/thread issue while logging the file.

+has anyone ever come across any of this?
+did i not do correctly on the log settings?
+can DailyRollingFileAppender actually handle this rollover issue?

please, this is rather headache to me and anyone would be kind enough to give me a pointer to overcome this. Thanks.

Wesley