How To Monitor Free Space in ASM Diskgroups

You have two methods to monitor free space in ASM diskgroups:

1. From SQL:

$ export ORACLE_SID=+ASM
$ export ORACLE_HOME=/u01/app/oracle/product/asm
$ sqlplus / as sysdba

SQL*Plus: Release 10.2.0.4.0 - Production on Mon May 25 18:23:55 2009

Copyright (c) 1982, 2007, Oracle. All Rights Reserved.
Connected to:
Oracle Database 10g Enterprise Edition Release 10.2.0.4.0 - Production
With the Partitioning, Real Application Clusters, OLAP, Data Mining
and Real Application Testing options

SQL> select name, state, total_mb, free_mb, usable_file_mb from v$asm_diskgroup;

NAME             STATE              TOTAL_MB         FREE_MB           USABLE_FILE_MB
--------             --------              --------------        -----------            ----------------------
DATA              MOUNTED       40946                  28602                  14301
FLASH            MOUNTED       20473                  20139                   20139


2. From asmcmd utility:

$ export ORACLE_SID=+ASM
$ export ORACLE_HOME=/u01/app/oracle/product/asm
$ sqlplus / as sysdba

$ asmcmd lsdg  

State Type Rebal Unbal Sector Block AU Total_MB Free_MB Req_mir_free_MB Usable_file_MB Offline_disks Name

MOUNTED  NORMAL     N   N   512   4096   1048576   40946   28602   0   14301   0   DATA/
MOUNTED  EXTERN       N   N   512   4096   1048576   20473   20139   0   20139   0   FLASH/