ASMCMD command

ASMCMD is a command line interface utility that allows DBA to check and manipulate files and directories within Automatic Storage Management (ASM) disks. It can perform different tasks, including search, create and remove directories, display some useful information about space utilization, etc.
In this post we'll consider some examples of ASMCMD usage.
First of all, we should bring an ASM instance up.
[oracle@localhost ~]$ cat do_asm
export ORACLE_SID=+ASM
export ORACLE_BASE=/u01/app/oracle/product/11.1.0
export ORACLE_HOME=/u01/app/oracle/product/11.1.0/asm
[oracle@localhost ~]$ source ~/do_asm
[oracle@localhost ~]$ sqlplus / as sysdba
SQL*Plus: Release 11.1.0.6.0
Copyright (c) 1982, 2007, Oracle.  All rights reserved.
Connected to an idle instance.
SQL> startup mount
ASM instance started
Total System Global Area  284565504 bytes
Fixed Size                  1299428 bytes
Variable Size             258100252 bytes
ASM Cache                  25165824 bytes
ASM diskgroups mounted
SQL> exit
Further, we'll consider different types of asmcmd command usage.
1. Enter ASMCMD:
[oracle@localhost ~]$ asmcmd
ASMCMD>
2. To list files/diskgroups in the current directory:
ASMCMD> ls
DATA/
DG_RECOV/
the same, but using wildcard(s):
ASMCMD> ls /*/*
+DATA/MYASMDB/ARCHIVELOG/2011_09_10/:
thread_1_seq_10.303.761509543
thread_1_seq_11.308.761510355
thread_1_seq_12.313.761511001
thread_1_seq_4.270.761501055
thread_1_seq_5.277.761503847
thread_1_seq_6.284.761503927
thread_1_seq_7.293.761504137
thread_1_seq_8.294.761504141
thread_1_seq_9.298.761507015
Current.260.760123743
Current.261.760123739
SYSAUX.257.760123487
SYSTEM.256.760123483
TEMP.268.760123809
UNDOTBS1.258.760123489
USERS.259.760123489
group_1.262.760123749
group_1.263.760123751
group_2.264.760123759
group_2.265.760123761
group_3.266.760123763
group_3.267.760123763
spfile.269.760123983
ASMCMD>
3. To navigate ASM directory:
ASMCMD> cd DATA/
ASMCMD> cd ..
4. To see the path of the current ASM directory:
ASMCMD> pwd
+DATA/MYASMDB
5. To create ASM directories:
ASMCMD> ls
MYASMDB/
STANDBY1/
ASMCMD> mkdir MyTest1
ASMCMD> ls
MYASMDB/
MyTest1/
STANDBY1/
ASMCMD>
6. The directories names are case insensitive:
ASMCMD> cd MYT*
ASMCMD> pwd
+DATA/MyTest1
ASMCMD>
7. To remove ASM directory:
ASMCMD> rm MYTEST1
ASMCMD> ls
MYASMDB/
STANDBY1/
ASMCMD>
8. List files and display their size and some extended information:
ASMCMD> ls -ls
Type      Redund  Striped  Time             Sys  Block_Size  Blocks      Bytes      Space  Name
DATAFILE  UNPROT  COARSE   SEP 10 18:00:00  Y          8192   73337  600776704  601882624  SYSAUX.257.760123487
DATAFILE  UNPROT  COARSE   SEP 10 18:00:00  Y          8192   88321  723525632  725614592  SYSTEM.256.760123483
DATAFILE  UNPROT  COARSE   SEP 10 18:00:00  Y          8192    5121   41951232   42991616  UNDOTBS1.258.760123489
DATAFILE  UNPROT  COARSE   SEP 10 18:00:00  Y          8192     641    5251072    6291456  USERS.259.760123489
9. Search the specified directory and all subdirectories in the ASM directory tree for the supplied name:
ASMCMD> find +DATA control*
+DATA/MYASMDB/CONTROLFILE/
+DATA/STANDBY1/CONTROLFILE/
ASMCMD>
ASMCMD> find -t CONTROLFILE +data *
+data/MYASMDB/CONTROLFILE/Current.260.760123743
+data/MYASMDB/CONTROLFILE/Current.261.760123739
+data/STANDBY1/CONTROLFILE/cf1
+data/STANDBY1/CONTROLFILE/current.271.761503123
+data/STANDBY1/CONTROLFILE/current.272.761503687
ASMCMD>
The -t flag tells to search for particular type of file(s), for example, CONTROLFILE.
The values for -t flag can be found in the type column of the V$ASM_FILE dictionary view.
10. Copy within ASM directory tree:
ASMCMD> ls
ARCHIVELOG/
CONTROLFILE/
DATAFILE/
ONLINELOG/
PARAMETERFILE/
TEMPFILE/
spfilemyasmdb.ora
ASMCMD> pwd
+DATA/MYASMDB
ASMCMD> cp +DATA/MYASMDB/spfilemyasmdb.ora +DATA/MYASMDB/copy_spfilemyasmdb.ora
source +DATA/MYASMDB/spfilemyasmdb.ora
target +DATA/MYASMDB/copy_spfilemyasmdb.ora
copying file(s)...
file, +DATA/myasmdb/copy_spfilemyasmdb.ora, copy committed.
ASMCMD> ls
ARCHIVELOG/
CONTROLFILE/
DATAFILE/
ONLINELOG/
PARAMETERFILE/
TEMPFILE/
copy_spfilemyasmdb.ora
spfilemyasmdb.ora
ASMCMD>
11. External copy, from ASM to OS filesystem:
ASMCMD>  cp +DATA/MYASMDB/spfilemyasmdb.ora /u01/app/oracle/product/11.1.0/asm/dbs/os_copy_spfilemyasmdb.ora
source +DATA/MYASMDB/spfilemyasmdb.ora
target /u01/app/oracle/product/11.1.0/asm/dbs/os_copy_spfilemyasmdb.ora
copying file(s)...
file, /u01/app/oracle/product/11.1.0/asm/dbs/os_copy_spfilemyasmdb.ora, copy committed.
ASMCMD> exit
[oracle@localhost ~]$ ll /u01/app/oracle/product/11.1.0/asm/dbs/os_copy_spfilemyasmdb.ora
-rw-r----- 1 oracle oinstall 3584 Mon dd hh:mm /u01/app/oracle/product/11.1.0/asm/dbs/os_copy_spfilemyasmdb.ora
[oracle@localhost ~]$
12. The opposite way, copy from OS filesystem to ASM will not work:
ASMCMD> cp /u01/app/oracle/product/11.1.0/asm/dbs/os_copy_spfilemyasmdb.ora +DATA/MYASMDB/asm_copy_spfilemyasmdb.ora
source /u01/app/oracle/product/11.1.0/asm/dbs/os_copy_spfilemyasmdb.ora
target +DATA/MYASMDB/asm_copy_spfilemyasmdb.ora
ASMCMD-08012: can not determine file type for file->'/u01/app/oracle/product/11.1.0/asm/dbs/os_copy_spfilemyasmdb.ora'
ORA-15056: additional error message
ORA-19762: invalid file type DGGetFileAttr20
ORA-06512: at "SYS.X$DBMS_DISKGROUP", line 207
ORA-06512: at line 3 (DBD ERROR: OCIStmtExecute)
ASMCMD>