ORA-27121

ORACLE:/home/oracle>su - txnmgr
Password:
DEV:/d02/txnmgr>sqlplus

SQL*Plus: Release 10.2.0.1.0 - Production on Fri Jul 24 17:15:40 2009

Copyright (c) 1982, 2005, Oracle. All rights reserved.

Enter user-name: ftuser
Enter password:
ERROR:
ORA-01034: ORACLE not available
ORA-27121: unable to determine size of shared memory segment
Linux Error: 13: Permission denied

solution:
ORACLE:/home/oracle>cd $ORACLE_HOME/bin
ORACLE:/d01/app/oracle/product/10.2.0/db_1/bin>chmod 6751 oracle
ORACLE:/d01/app/oracle/product/10.2.0/db_1/bin>

Enter user-name: ftuser
Enter password:

Connected to:
Oracle Database 10g Enterprise Edition Release 10.2.0.1.0 - Production
With the Partitioning, OLAP and Data Mining options

SQL> select * from dual;

D
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