When you install a single instance or RAC on a linux machine always you have to disable SElinux!! On the other hand RMAN with shell scripts and crontab appeared to be more efficient! In case of a reboot always you have to start manualy the OEM! with automated scripts in crontab you do not have to worry about this!
Regards
panos
When following the installation manual for apex 4.0.1 and installing Apex 4.0.1 with the embedded PL/SQL Gateway, a wrong url is specified in the Apex installation documentation.