As a DBA, you may find the Performance page of Oracle Enterprise Manager (11g and 12c) very useful. However when you click the Performance tab on the Oracle Enterprise Manager, you may find the scree like this:
One of the solution is to install the flash plugin manually. Here are the steps to do it on Linux server (Redhat linux 5/6, Oracle Linux 5/6)
1. Download the following rpm : flash-plugin-184.108.40.206-release.x86_64.rpm
2. As root user, Install this rpm on the server that runs the browser for Enterprise Manager console:
rpm -ivh flash-plugin-220.127.116.11-release.x86_64.rpm.
3. Until this point, you may think you have already installed the Flash player Plugin. But not really, if you click the performance tab,you would still be asked to install the flash plugin. why?
4. The issue is that the blowser like firefox still looks for the flash player plugin library libflashplayer.so in
/usr/lib64/flash-plugin/ while the installation of flash-plugin-18.104.22.168-release.x86_64.rpm put the this library in /usr/lib/mozilla/plugins
So the solution is to put the softlink for it:
ln -s /usr/lib64/flash-plugin/libflashplayer.so /usr/lib/mozilla/plugins/libflashplayer.so
5. Now when you click the Performance tab, you are able to see the clear picture of the database performance page: