I have just migrated web application from Tomcat6 to Tomcat7. But after this errors that appeared in application are logged to 'stderr.log' file. When I have used Tomcat6 errors and output were logged to 'stdout.log' file. So I was able to see every information I need in one(stdout.log) file.
How to 'tell' Tomcat7 to log errors and output to 'stdout.log' file as it was in Tomcat6?
If you're referring to webapp logging, webapps should not be logging to either stdout or stderr. Use a "real" logger such as the java.util.log (JULI) logger and define each webapp's logger as part of the webapp itself.
For Tomcat's own server event logging, purposes, several loggers apply. Most useful is the catalina.out file, which, in fact usually contains a redirect of the Tomcat JVM's own internal System.out and System.err streams, among other things.
Tomcat's exact logging channels are configurable and for certain type of Tomcat configurations, may not use catalina.out, especially on some of the Windows versions.
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