Exadata Storage Configuration

 Laptop

   ↓

SSH → Storage Cell (celladmin)

   ↓

CellCLI

   ↓

PhysicalDisk

   ↓

CellDisk

   ↓

GridDisk (DATA / RECO / SPARSE)

   ↓

DB Node (oracle user)

   ↓

ASM Diskgroup

   ↓

Database Files

Quarter Rack – How Much Physical Storage Do You Get?

⚠ Important: Exact size depends on:

• Exadata generation (X8, X9M, X10M…)

• High Capacity (HC) or Extreme Flash (EF)

• Disk size (10TB, 14TB, 18TB etc.)

But let’s take a typical High Capacity Quarter Rack example.

Typical Quarter Rack (HC Model)

• 3 Storage Cells

• Each cell ≈ 12 HDD disks

• Each HDD ≈ 14TB (example modern config)

So per cell:

12 × 14TB = 168TB raw

For 3 cells:

168TB × 3 = 504TB raw physical storage

⚠ This is RAW capacity.

🔹 STEP 1 – Login to Storage Cell

🔸 Where?

From your laptop or DB node

🔸 Command:

ssh celladmin@cell01

🔸 Output:

[celladmin@cell01 ~]$

You are now inside the storage server.

🔹 STEP 2 – Start CellCLI

cellcli

🔸 Output:

CellCLI>

Now you are inside storage management console.

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🔹 STEP 3 – Check Physical Disks

CellCLI> list physicaldisk

🔸 Sample Output:

         name              status   size     slotNumber
         PD_00_cell01     normal   14.6T    0
         PD_01_cell01     normal   14.6T    1
         ...
         PD_11_cell01     normal   14.6T    11

✔ These are real hardware disks.

---

🔹 STEP 4 – Check CellDisks

CellCLI> list celldisk

🔸 Sample Output:

         name              size     status
         CD_00_cell01     14.6T    normal
         CD_01_cell01     14.6T    normal
         CD_02_cell01     14.6T    normal

✔ Each physical disk has one CellDisk.

---

🔹 STEP 5 – Check Free Space

CellCLI> list celldisk attributes name,size,freespace

🔸 Output:

name            size    freespace
CD_00_cell01    14.6T   14.6T
CD_01_cell01    14.6T   14.6T

✔ Entire disk is free.

---

🔹 STEP 6 – Create GridDisk (DATA)

🔸 Where?

Inside storage cell (CellCLI> prompt)

CellCLI> create griddisk DATA_CD_00 celldisk=CD_00_cell01

🔸 Output:

GridDisk DATA_CD_00 successfully created

✔ GridDisk carved from CellDisk.

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🔹 STEP 7 – Create GridDisk (RECO)

CellCLI> create griddisk RECO_CD_00 celldisk=CD_00_cell01 size=4T

🔸 Output:

GridDisk RECO_CD_00 successfully created

---

🔹 STEP 8 – Verify GridDisks

CellCLI> list griddisk

🔸 Output:

name            celldisk        size     status
DATA_CD_00      CD_00_cell01    10.6T    active
RECO_CD_00      CD_00_cell01    4T       active

✔ Now CellDisk space is divided.

---

🔹 STEP 9 – Exit Storage Cell

CellCLI> exit

You are back to:

[celladmin@cell01 ~]$

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🔹 STEP 🔟 – Go to DB Node

ssh oracle@dbnode01

Output:

[oracle@dbnode01 ~]$

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🔹 STEP 11 – Check ASM Sees GridDisks

asmcmd lsdsk

🔸 Output:

Path
o/192.168.10.1/DATA_CD_00
o/192.168.10.1/RECO_CD_00
o/192.168.10.2/DATA_CD_01
o/192.168.10.3/DATA_CD_02

✔ ASM sees disks from all storage cells.

---

🔹 STEP 12 – Create ASM Diskgroup (DATA)

Login to SQL:

sqlplus / as sysasm

CREATE DISKGROUP DATA
NORMAL REDUNDANCY
DISK
'o/192.168.10.1/DATA_CD_00',
'o/192.168.10.2/DATA_CD_01',
'o/192.168.10.3/DATA_CD_02';

🔸 Output:

Diskgroup created.

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🔹 STEP 13 – Verify Diskgroup

select name, total_mb, free_mb from v$asm_diskgroup;

🔸 Output:

NAME   TOTAL_MB   FREE_MB
DATA   178000000  177500000
RECO    70000000   69950000

✔ Storage ready for database files.

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🔹 STEP 14 – Create SPARSE (Optional)

🔸 Back to Storage Cell

ssh celladmin@cell01
cellcli

CellCLI> create griddisk SPARSE_CD_00 celldisk=CD_00_cell01 sparse=true

Output:

GridDisk SPARSE_CD_00 successfully created

---

🔸 Back to DB Node

CREATE DISKGROUP SPARSE_DG
NORMAL REDUNDANCY
DISK 'o/.../SPARSE_CD_00'
ATTRIBUTE 'thin_provisioned'='true';

Output:

Diskgroup created.

✔ Sparse ready for snapshot DB.

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