Oracle - Unable to access ASMCMD (DBD ERROR: OCISessionBegin)

Error:

$ asmcmd
ORA-01034: ORACLE not available
ORA-27101: shared memory realm does not exist
Linux Error: 2: No such file or directory (DBD ERROR: OCISessionBegin)
ASMCMD-08103: failed to connect to ASM; ASMCMD running in non-clustered mode

Cause:

The ASM database has not been started

Resolution:

Restart the ASM database then log into asmcmd to make sure it has started.

Check that the ORACLE_SID and ORACLE_HOME are pointing towards ASM, if not then set them correctly:

$ echo $ORACLE_SID
+ASM
$ echo $ORACLE_HOME
/u01/oracle/asm102

Check that the ASM database is running:

$ sqlplus ‘/as sysdba’
SQL*Plus: Release 10.2.0.4.0 - Production on Mon Oct 18 11:08:39 2010
Copyright (c) 1982, 2007, Oracle. All Rights Reserved.
Connected to an idle instance.
SQL>

Startup ASM database

SQL> startup

Log into ASMCMD

$ asmcmd
ASMCMD>