Convert oracle asm disk from member to candiate

In order to convert the member asm disk to candiate we need to first clear the contents of the disk and then remove and add again.

In this example we are converting CRS1 and CRS2 from member to candidate.

steps are:

[root@rac1 ~]# dd if=/dev/zero of=/dev/sdl1 bs=1024 count=100
100+0 records in
100+0 records out
102400 bytes (102 kB) copied, 0.0349507 s, 2.9 MB/s
[root@rac1 ~]#
[root@rac1 ~]# oracleasm deletedisk CRS1
Disk "CRS1" defines an unmarked device
Dropping disk: done
[root@rac1 ~]#
[root@rac1 ~]# oracleasm createdisk CRS1 /dev/sdl1
Writing disk header: done
Instantiating disk: done
[root@rac1 ~]#

[root@rac1 ~]# dd if=/dev/zero of=/dev/sdm1 bs=1024 count=100
100+0 records in
100+0 records out
102400 bytes (102 kB) copied, 0.0166484 s, 6.2 MB/s
[root@rac1 ~]#
[root@rac1 ~]#
[root@rac1 ~]# oracleasm deletedisk CRS2
Disk "CRS2" defines an unmarked device
Dropping disk: done
[root@rac1 ~]#
[root@rac1 ~]# oracleasm createdisk CRS2 /dev/sdm1
Writing disk header: done
Instantiating disk: done
[root@rac1 ~]#
[root@rac1 ~]# oracleasm listdisks
ASM1
ASM2
ASM3
ASM4
ASM5
ASM6
ASM7
ASM8
CRS1
CRS2
[root@rac1 ~]#

After this we can see that CRS1 and CRS2 are now candidate disks

If you are wondering that how did not know what disk is linked with CRS1 and CRS2 then see my post "determine the path behind the oracle asm disk"