ASMCMD useful commands

One small article on ASMCMD commands which can help you in day to day ASM Command-Line tasks.

1. Let’s check ASMCMD’s version.

[oracle@dbnode1 ~]$ asmcmd -V
asmcmd version 11.2.0.0.0
Let’s enter into ASMCMD Command-Line utility.

[oracle@dbnode1 ~]$ asmcmd

ASMCMD>
Now We are in ASMCMD Command-Line utility. We will now see few asmcmd commands about diskgroups.

2. To list the diskgroups we have.

ASMCMD> lsdg
State Type Rebal Sector Block AU Total_MB Free_MB Req_mir_free_MB Usable_file_MB Offline_disks Voting_files Name
MOUNTED EXTERN N 512 4096 1048576 18426 15138 0 15138 0 N DATA/
So here we see information like State, Type of redundancy, Total and Free MB, Name, etc.. But with lsdg command, we won’t get the details of the diskgroups which is unmounted from ASM.

3. To check details of all the diskgroups, i.e. Mounted and Dismounted, We would use lsdg command with “–– discovery” argument.

ASMCMD> lsdg –discovery
State Type Rebal Sector Block AU Total_MB Free_MB Req_mir_free_MB Usable_file_MB Offline_disks Voting_files Name
MOUNTED EXTERN N 512 4096 1048576 18426 15138 0 15138 0 N DATA/
DISMOUNTED N 512 4096 0 0 0 0 0 0 N FRA/
So now we can also see the details of diskgroup which is Dismounted, i.e. FRA

4. To mount a diskgroup in ASMCMD, we will try mounting FRA diskgroup.

ASMCMD> mount FRA
Command executed without an error.

List diskgroups now,

5. To list a particular diskgroup.

ASMCMD> lsdg DATA
State Type Rebal Sector Block AU Total_MB Free_MB Req_mir_free_MB Usable_file_MB Offline_disks Voting_files Name
MOUNTED EXTERN N 512 4096 1048576 18426 15138 0 15138 0 N DATA/

6. To list Mounted ASM disks.

ASMCMD> lsdsk
Path
/dev/oracleasm/disks/DATA01
/dev/oracleasm/disks/FRA01

7. To check details of ASM disks.

ASMCMD> lsdsk -k
Total_MB Free_MB OS_MB Name Failgroup Library Label UDID Product Redund Path
18426 15138 18426 DATA01 DATA01 ASM Library – Generic Linux, version 2.0.12 (KABI_V2) DATA01 UNKNOWN /dev/oracleasm/disks/DATA01
8189 7654 8189 FRA01 FRA01 ASM Library – Generic Linux, version 2.0.12 (KABI_V2) FRA01 UNKNOWN /dev/oracleasm/disks/FRA01
Here we can see total size, free size and OS level size in MB. Label and path of the disk. We can see Redund Status is UNKNOWN which means there is no ASM redundancy available for these disks.

8. To check information for a particular disk.

ASMCMD> lsdsk -k -G DATA
Total_MB Free_MB OS_MB Name Failgroup Library Label UDID Product Redund Path
18426 15138 18426 DATA01 DATA01 ASM Library – Generic Linux, version 2.0.12 (KABI_V2) DATA UNKNOWN /dev/oracleasm/disks/DATA01
Now it’s showing details of “DATA01” disk only.

9. To get Input/Output State details of disks.

ASMCMD> iostat
Group_Name Dsk_Name Reads Writes
DATA DATA01 5450240 12764160
FRA FRA01 98304 4096
Here Group_Name shows, which ASM diskgroup this disk belongs to. We can see Reads/Writes information in bytes.

10. To check above details for a particular Disk.

ASMCMD> iostat -G FRA
Group_Name Dsk_Name Reads Writes
FRA FRA01 98304 4096
11. To retrieve information of Reads/Writes Error.

ASMCMD> iostat -e
Group_Name Dsk_Name Reads Writes Read_Err Write_Err
DATA DATA01 5450240 13280256 0 0
FRA FRA01 98304 4096 0 0
This will show you IO erros of disk.

12. To get Time Statistics, Read Time & Write Time.

ASMCMD> iostat -e -t
Group_Name Dsk_Name Reads Writes Read_Err Write_Err Read_Time Write_Time
DATA DATA01 5450240 13624320 0 0 .811 1.37
FRA FRA01 98304 4096 0 0 .011 0

13. To get information about OracleASM ServerParameter file.

ASMCMD> spget
+DATA/rc-scan/asmparameterfile/registry.253.986765603
This will show you the location of spfile for ASM instance.

14. To List the current directory.

ASMCMD> ls -l
State Type Rebal Name
MOUNTED EXTERN N DATA/
MOUNTED EXTERN N FRA/
15. To navigate to sub-directory.

ASMCMD> cd DATA
ASMCMD> ls -l
Type Redund Striped Time Sys Name
Y PRTDB/
Y rc-scan/
Here we can see sub-directories under DATA directory.
‘Y’ flag under Sys colunmn shows, sub-directories are owned by SYS user.

16. To print current directory path in ASMCMD Command-Line utility, connect ASMCMD using -p argument.

[oracle@dbnode1 ~]$ asmcmd -p

ASMCMD [+] >

We can see It is showing ‘+’ that is Root Directory.
Let’s navigate to sub-directory.

ASMCMD [+] > ls
DATA/
FRA/
ASMCMD [+] > cd +DATA/PRTDB/DATAFILE
ASMCMD [+DATA/PRTDB/DATAFILE] > ls
EXAMPLE.264.986768097
SYSAUX.257.986767995
SYSTEM.256.986767993
TBS.269.986769231
UNDOTBS1.258.986767995
UNDOTBS2.265.986768163
USERS.259.986767995
Here we can see current directory “ASMCMD [+DATA/PRTDB/DATAFILE] >” Even after navigating to subdirectory.

We are now in datafile directory of PRTDB database.

17. To check permissions on file.

ASMCMD [+DATA/PRTDB/DATAFILE] > ls –permission
User Group Permission Name
rw-rw-rw- EXAMPLE.264.986768097
rw-rw-rw- SYSAUX.257.986767995
rw-rw-rw- SYSTEM.256.986767993
rw-rw-rw- TBS.269.986769231
rw-rw-rw- UNDOTBS1.258.986767995
rw-rw-rw- UNDOTBS2.265.986768163
rw-rw-rw- USERS.259.986767995
18. To check disk usage.

ASMCMD [+DATA] > du
Used_MB Mirror_used_MB
3154 3154
19. To find file with name.

ASMCMD [+DATA] > find + system*
+DATA/PRTDB/DATAFILE/SYSTEM.256.986767993
Here we found file containing system in its name.

20. To list currently open files by all instances in ASM Use Below Command.

ASMCMD [+] > lsof
DB_Name Instance_Name Path
PRTDB PRTDB +DATA/PRTDB/CONTROLFILE/current.265.987302781
PRTDB PRTDB +DATA/PRTDB/DATAFILE/sysaux.269.987302597
PRTDB PRTDB +DATA/PRTDB/DATAFILE/system.261.987302651
PRTDB PRTDB +DATA/PRTDB/DATAFILE/undotbs1.268.987302719
PRTDB PRTDB +DATA/PRTDB/DATAFILE/users.272.987302717
PRTDB PRTDB +DATA/PRTDB/ONLINELOG/group_1.264.987302785
PRTDB PRTDB +DATA/PRTDB/ONLINELOG/group_2.263.987302789
PRTDB PRTDB +DATA/PRTDB/ONLINELOG/group_3.262.987302793
PRTDB PRTDB +DATA/PRTDB/TEMPFILE/temp.273.987302813
PRTDB PRTDB +FRA/PRTDB/CONTROLFILE/current.256.987302781
PRTDB PRTDB +FRA/PRTDB/ONLINELOG/group_1.259.987302787
PRTDB PRTDB +FRA/PRTDB/ONLINELOG/group_2.258.987302791

Akhash Ramnath