root:/u01/oracle/product/18.104.22.168 --> sqlplus v500/v500
SQL*Plus: Release 22.214.171.124.0 - Production on Thu May 13 14:25:09 2004
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ORA-27123: unable to attach to shared memory segment
IBM AIX RISC System/6000 Error: 13: Permission denied
There could be a couple of reasons why you get this error.
First, I'd check to make sure that your SGA does not exceed SHMMAX in /etc/system. If that is the case, then increase SHMMAX and reboot the server or decrease your SGA and restart the instance.
Second, check your file permissions. You can set things by doing the following:
umask 022 cd $ORACLE_HOME chmod 755 (on all sub-dirs) cd $ORACLE_BASE/admin/(SID NAME) chmod 755 (on all sub-dirs) cd $ORACLE_HOME/bin chmod 6751 oracle
You should be able to connect once all of the above is done.
This was first published in June 2004