You may want to delete all data on a disk, and then use the disk for another purpose.

1. Use the CellCLI LIST command to display the Exadata Storage Server objects on the disk.

   For example, you can use the LIST PHYSICALDISK command to view the full list of physical disk devices.

   CellCLI> LIST PHYSICALDISK
            20:0   D174LX    normal
            20:1   D149R0    normal
            ...
   

   You can also use the LIST LUN command to view information about the LUN residing on each physical disk. For example:

   CellCLI> LIST LUN WHERE physicalDrives='20:0' DETAIL
     name:              0_0
     deviceName:        /dev/sda
     diskType:          HardDisk
     id:                0_0
     isSystemLun:       TRUE
     lunSize:           557.861328125G
     lunUID:            0_0
     physicalDrives:    20:0
     raidLevel:         0
     lunWriteCacheMode: "WriteBack, ReadAheadNone, Direct, No Write Cache if Bad BBU"
     status:            normal
   

   You can use the LIST DISKMAP command to view information about the cell disk and grid disks that reside on each device. For example:

   # cellcli -e "list diskmap" | grep 20:0
   
      20:0            K68DWJ          0                       normal  559G
      CD_00_burd01celadm01    /dev/sda3   
      "DATAC1_CD_00_burd01celadm01, RECOC1_CD_00_burd01celadm01"

2. From Oracle ASM, drop the Oracle ASM disks on the hard disk using the following command:

   SQL> ALTER DISKGROUP diskgroup_name DROP DISK asm_disk_name;

3. From Exadata Storage Server, drop the cell disks and grid disks on the hard disk using the following command:

   CellCLI> DROP CELLDISK celldisk_on_this_lun FORCE

   Note:

   To overwrite all data on the cell disk, use the ERASE option with the DROP CELLDISK command. The following is an example of the command:

   CellCLI> DROP CELLDISK CD_03_cell01 ERASE=1pass NOWAIT
   
   CellDisk CD_03_cell01 erase is in progress

   If the hardware component supports cryptographic erasure, it is automatically used to provide optimal security and erasure performance. For example:

   CellCLI> DROP CELLDISK CD_03_cell01 erase=7pass FORCE; 
   
   Because cell disks CD_03_cell01 qualify for crypto erasure, the more efficient 
   crypto erasure method will be used instead of the specified multipass overwrite method. 
   
   Cell disks CD_03_cell01 have been successfully crypto-erased. 
   CellDisk CD_03_cell01 successfully dropped

   Each erasure operation generates a certificate under /var/log/cellos/, which certifies that the hardware component was erased securely.

4. Drop the drive for hot removal. For example:

   CellCLI> ALTER PHYSICALDISK 20:0 DROP FOR REPLACEMENT

5. Ensure the blue OK to Remove LED on the disk is lit before removing the disk.

   Caution:

   Ensure the disk blue LED is turned on before removing the drive. Do not remove the drive if the disk blue LED is unlit, or it may cause your system to crash.

6. Remove the disk to be repurposed, and insert a new disk.
7. Wait for the new hard disk to be added as a LUN.

   CellCLI> LIST LUN

   The cell disks and grid disks are automatically be created on the new hard disk, and the grid disks are added to the Oracle ASM group.