Why I got ORA-27121: unable to determine size of
shared memory segment ?
A. The full erros stack:
ERROR:
ORA-01034: ORACLE not available
ORA-27121: unable to determine size of shared memory
segment
Linux Error: 13: Permission denied
This is caused by Oracle installer not setting setuid
on $ORACLE_HOME/bin/oracle.
To fix do:
$ cd $ORACLE_HOME/bin
$ chmod 6751 oracle