Sometimes you may need to map ASM Disks to its physical devices.
If they are based on ASMLib you will see their ASM name, ie: ORCL:VOL1 when querying v$asm_disk
When running oracleasm querydisk VOL1 you will get in addition the major - minor numbers, that can be used to match the physical device, ie:
[root@orcldb2 ~]# /etc/init.d/oracleasm querydisk VOL1
Disk "VOL1" is a valid ASM disk on device [8, 97]
[root@orcldb2 ~]# ls -l /dev | grep 8, | grep 97
brw-rw---- 1 root disk 8, 81 Nov 4 13:02 sdg1
This script can do the job for a group of ASM Disks:---------- start here ------------
#!/bin/ksh
for i in `/etc/init.d/oracleasm listdisks`
do
v_asmdisk=`/etc/init.d/oracleasm querydisk $i | awk '{print $2}'`
v_minor=`/etc/init.d/oracleasm querydisk $i | awk -F[ '{print $2}'| awk -F] '{print $1}' | awk '{print $1}'`
v_major=`/etc/init.d/oracleasm querydisk $i | awk -F[ '{print $2}'| awk -F] '{print $1}' | awk '{print $2}'`
v_device=`ls -la /dev | grep $v_minor | grep $v_major | awk '{print $10}'`
echo "ASM disk $v_asmdisk based on /dev/$v_device [$v_minor $v_major]"
done
---------- finish here ------------
The output looks like this:ASM disk "VOL1" based on /dev/sdg1 [8, 97]
ASM disk "VOL10" based on /dev/sdp1 [8, 241]
ASM disk "VOL2" based on /dev/sdh1 [8, 113]
ASM disk "VOL3" based on /dev/sdk1 [8, 161]
ASM disk "VOL4" based on /dev/sdi1 [8, 129]
ASM disk "VOL5" based on /dev/sdl1 [8, 177]
ASM disk "VOL6" based on /dev/sdj1 [8, 145]
ASM disk "VOL7" based on /dev/sdn1 [8, 209]
ASM disk "VOL8" based on /dev/sdo1 [8, 225]
ASM disk "VOL9" based on /dev/sdm1 [8, 193]
If you are using multi-path, you will need an additional step to map the physical device to the multi-path device, for instance if using EMC Powerpath if you want to map sdf1
[root@orclp ~]# /etc/init.d/oracleasm querydisk vol1
Disk "VOL1" is a valid ASM disk on device [8, 81]
[root@orclp ~]# ls -l /dev | grep 8,| grep 81
brw-rw---- 1 root disk 8, 81 Oct 29 20:42 sdf1
[root@orclp ~]# powermt display dev=all
...
...
Pseudo name=emcpowerg
Symmetrix ID=000290101698
Logical device ID=0214
state=alive; policy=SymmOpt; priority=0; queued-IOs=0
==============================================================================
---------------- Host --------------- - Stor - -- I/O Path - -- Stats ---
### HW Path I/O Paths Interf. Mode State Q-IOs Errors
==============================================================================
1 qla2xxx sdf FA 7bB active alive 0 0
2 qla2xxx sdq FA 10bB active alive 0 0
...
...
The last step is to check the partition assigned to the emcpower device, ie:[root@orclp ~]# ls -l /dev/emcpowerg*
brw------- 1 root root 120, 96 Oct 29 20:41 /dev/emcpowerg
brw------- 1 root root 120, 97 Nov 15 13:08 /dev/emcpowerg1
