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See TomcatCreateNativeLaunchers

How do I rotate catalina.out?

Honestly, the first question is "why are you rotating catalina.out"? Tomcat logs very little to catalina.out so the usual culprit is web applications that stupidly send output to System.out or System.err. If that's the case, what you ought to do is set swallowOutput="true" on the application's <Context> configuration. That will send the output to a file configured (default) by conf/logging.properties. Once you've done that, get the application fixed to use a real logger, or at least use ServletContext.log().

If you've decided that you still absolutely positively need to rotate catalina.out, there is something that you have to understand: catalina.out is created by your shell's output redirection, just like when you type "ls -l > dir_listing.txt". So rotating the file needs to be done carefully.

You can't just re-name the file or you'll find that Tomcat will continue logging to the file under the new name. You also can't delete catalina.out and re-create it, or you'll never get anything logged to catalina.out after that, unless you restart Tomcat.

There are really only two ways to properly rotate catalina.out, and they both have downsides.

Rotate catalina.out using logrotate (or similar)

To use a tool like [logrotate|http://linuxcommand.org/man_pages/logrotate8.html], you'll want to use the "copytruncate" configuration option. This will copy catalina.out to another file (like catalina.out.\[datestamp\]) and then truncates catalina.out to zero-bytes. There is a major downside to this if catalina.out is seeing a lot of action: some log messages written to the log file during the copy/truncate procedure may be lost.

Rotate catalina.out using rotatelogs or chronolog (or similar)

To use a tool like Apache httpd's rotatelogs or chronolog, you'll have to modify Tomcat's catalina.sh (or catalina.bat) script to change the output redirection from a redirect to a pipe. The existing code in catalina.sh looks like this:

    eval "\"$_RUNJAVA\"" "\"$LOGGING_CONFIG\"" $LOGGING_MANAGER $JAVA_OPTS $CATALINA_OPTS \
      -Djava.endorsed.dirs="\"$JAVA_ENDORSED_DIRS\"" -classpath "\"$CLASSPATH\"" \
      -Djava.security.manager \
      -Djava.security.policy=="\"$CATALINA_BASE/conf/catalina.policy\"" \
      -Dcatalina.base="\"$CATALINA_BASE\"" \
      -Dcatalina.home="\"$CATALINA_HOME\"" \
      -Djava.io.tmpdir="\"$CATALINA_TMPDIR\"" \
      org.apache.catalina.startup.Bootstrap "$@" start \
      >> "$CATALINA_OUT" 2>&1 "&"

You'll need to change that to something which looks more like this:

    eval "\"$_RUNJAVA\"" "\"$LOGGING_CONFIG\"" $LOGGING_MANAGER $JAVA_OPTS $CATALINA_OPTS \
      -Djava.endorsed.dirs="\"$JAVA_ENDORSED_DIRS\"" -classpath "\"$CLASSPATH\"" \
      -Djava.security.manager \
      -Djava.security.policy=="\"$CATALINA_BASE/conf/catalina.policy\"" \
      -Dcatalina.base="\"$CATALINA_BASE\"" \
      -Dcatalina.home="\"$CATALINA_HOME\"" \
      -Djava.io.tmpdir="\"$CATALINA_TMPDIR\"" \
      org.apache.catalina.startup.Bootstrap "$@" start \
      | "$PATH_TO_CHRONOLOG" $CATALINA_BASE/logs/catalina.out.%Y-%m-%d

This will be somewhat similar for catalina.bat, but the actual launch command will look different.

Also note that there are currently two places in catalina.sh (and catalina.bat) where Tomcat is launched, depending upon whether you are using a security manager or not. You should read the whole catalina.sh (or catalina.bat) file to make sure you have handled every case where Tomcat is launched.

Configuration

How do I set up multiple sites sharing the same war application/war file?

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