Uninstall OBIEE 11g on Linux

From OBIEE installation run ($ORACLE_HOME/oui/bin):
fmw/Oracle_BI1//oui/bin/runInstaller -deinstall

Save the settings for silent uninstaller as described here:

http://docs.oracle.com/cd/E23943_01/bi.1111/e10539/c6_deinstall.htm#autoId20
./runInstaller -silent -deinstall -response path_to_deinstall_instance_file/deinstall_instance_filename.rsp