# Manage Storage Pools and Drives

In `Settings-Storage`, you can view storage pool capacity and drive health, create or expand storage pools, manage SSD cache, and run S.M.A.R.T. tests. `Storage` can be expanded in the left menu and contains two pages: `Storage Pool` and `HDD/SSD`.

## View Storage Pool Status and Capacity

1. Open `Settings-Storage-Storage Pool`:
   ![Storage pool list](position://apps/settings/storage#storage-pool-list)
2. View the storage pool name, storage mode, used capacity, and total capacity on the storage pool card. The storage pool name distinguishes different pools; the storage mode shows whether the pool uses RAID, JBOD, Basic, or another mode; used capacity shows the occupied space; total capacity shows the overall available capacity of the storage pool.
3. Check the storage pool status. When the status is `Normal`, the storage pool is available.
4. View the drives associated with the storage pool. The drive names and capacities associated with the storage pool appear below the storage pool card.

## Create a Storage Pool

Creating a storage pool formats the selected drives and clears the data on them. Before you begin, make sure the drives do not contain data you need to keep.

1. Open `Settings-Storage-Storage Pool`.
2. Click [Create Storage Pool].
3. In `1.Select Disks`, select available drives. Available drives are grouped by `SATA DISK`; after a drive is selected, a purple check mark appears in the upper-right corner of the card:
   ![Create storage pool - select disks](position://apps/settings/storage#create-pool-select-disks)
4. In `2.Select storage mode`, select a storage mode. Available storage modes depend on the number of selected drives; modes that do not meet the drive-count requirement appear in the `No selectable modes` group:
   ![Create storage pool - select storage mode (1 disk)](position://apps/settings/storage#create-pool-select-mode)
   ![Create storage pool - select storage mode (2 disks)](position://apps/settings/storage#create-pool-select-mode-2-disks)
   The minimum drive requirements for storage modes are as follows:
   - `Basic`: only appears when 1 drive is selected; it does not appear in available modes when 2 or more drives are selected.
   - `JBOD`: 1 or more drives.
   - `RAID 0`: `Requires at least 2 hard drives`.
   - `RAID 1`: `Requires at least 2 hard drives`.
   - `RAID 5`: `Requires at least 3 hard drives`.
   - `RAID 6`: `Requires at least 4 hard drives`.
   - `RAID 10`: `Requires at least 4 hard drives and the number must be even`.

5. Check `Estimated Capacity` at the bottom, confirm the capacity estimate for the selected drives and storage mode, then click [Next].
6. Set the capacity quota for each user on this storage pool:
   ![Create storage pool - user quota settings](position://apps/settings/storage#create-pool-user-quota)
   The default quota is `Unlimited`; to set a limit, change the input box in the corresponding user row to a GB value.
7. Click [Next], then confirm the risk in the `Format Warning` dialog. The dialog warns that formatting the selected drives permanently deletes all data on them and cannot be undone. The buttons are [Cancel] and [Format]:
   ![Format warning dialog](position://apps/settings/storage#format-warning-dialog)
8. After clicking [Format], enter the current administrator password in the `Password Verification` dialog. The dialog prompts `Please enter the password for account admin to continue.`, and the buttons are [Cancel] and [Confirm]:
   ![Password verification dialog](position://apps/settings/storage#password-verify-dialog)
9. Click [Confirm] and wait for creation to finish. The progress dialog title is `Create Storage Pool`, the status is `Initializing storage pool`, and the prompt is `Do not remove drives or shut down the system. The process is expected to take 2 to 5 minutes.`:
   ![Create storage pool progress](position://apps/settings/storage#create-pool-progress)
10. Return to the `Storage Pool` list and confirm that the new storage pool appears. The new storage pool appearing in the list indicates that creation succeeded.

Both creating and deleting a storage pool open the `Password Verification` dialog, but the lower-right button text differs: the creation flow uses [Confirm], and the deletion flow uses [Verify].

## Expand a Storage Pool

The `Expand Storage Pool` entry is in the `...` menu on the right side of the storage pool card. When unused drives exist in the system, a JBOD storage pool shows the [Expand Storage Pool] entry; RAID 0 storage pools do not support expansion and do not show this entry.

1. Open `Settings-Storage-Storage Pool`.
2. Click `...` on the right side of a storage pool card that supports expansion.
3. Click [Expand Storage Pool]:
   ![Expand storage pool dialog](position://apps/settings/storage#extend-pool-dialog)
4. In the `Expand Storage` dialog, select an unused drive that can be used for expansion.
5. After confirming the selection, click [Confirm].

## Manage SSD Cache

1. Open `Settings-Storage-Storage Pool`.
2. Click `...` on the right side of the target storage pool card.
3. Click [SSD cache management]:
   ![SSD cache management dialog](position://apps/settings/storage#ssd-cache-dialog)
4. In the `SSD Cache-<storage pool name>` dialog, view the available cache. If there is currently no SSD available for cache, the dialog shows `No SSD Cache Available` and states “Create an SSD cache for the storage pool to enhance read and write performance”. The interface also prompts “(Only SSDs larger than 32GB can be used for caching)”. At this time, the [Confirm] button is unavailable, and you can only click [Cancel] to close the dialog.
5. If available SSDs exist, first select a cache type in `Cache mode`. Options include `Read-only (requires at least one SSD)` and `Read-write (requires at least two SSDs of the same type)`:
   ![SSD cache - with available SSD](position://apps/settings/storage#ssd-cache-dialog-with-ssd)
6. In the `Select Disks` area, select the SSDs used for cache.
7. In `Please select cache acceleration mode`, select an acceleration mode. After selecting read-only cache and selecting one SSD, the available acceleration mode is `Basic`.
8. After the cache mode, SSDs, and cache acceleration mode are all selected, the [Confirm] button becomes available. Click [Confirm] to submit the current SSD cache configuration.

## Delete a Storage Pool

Deleting a storage pool clears all data in it. Before the operation, make sure you have backed up the content you need to keep.

1. Open `Settings-Storage-Storage Pool`.
2. Click `...` on the right side of the target storage pool card, then click [Delete Storage Pool].
3. Read the risk prompt in the `Delete Storage Pool` dialog:
   ![Delete storage pool confirmation dialog](position://apps/settings/storage#delete-pool-dialog)
   The dialog prompts:
   - `1.Deleting the storage pool will erase all data stored in it`
   - `2.All SSD caches and hot spares associated with this storage pool will also be removed.`
4. Click [Confirm] to proceed to password verification:
   ![Password verification dialog](position://apps/settings/storage#password-verify-dialog)
   During deletion, the password verification dialog prompts `If resources are in use, the NAS needs to restart to complete storage pool deletion`, and asks you to enter the password for account `admin` to continue. The buttons are [Cancel] and [Verify]. Unlike the create storage pool flow, the lower-right button in the deletion flow is [Verify].
5. Enter the password and click [Verify]. During deletion, the storage pool status shows `Deleting…`.
6. When the storage pool disappears from the list, deletion is complete; after deletion, the previously associated drives return to the `Not used` group on the `HDD/SSD` page.

## View HDD/SSD Information

1. Open `Settings-Storage-HDD/SSD`:
   ![HDD and SSD list](position://apps/settings/storage#disk-list)
2. The page displays drives grouped by storage pool.
3. View basic drive information. Each drive row is used to view the basic information and health status of the drive.
4. View the `Not used` group. Drives that have not been added to a storage pool appear under `Not used`.
5. Check drive status. When the status is `Normal`, the drive health status is normal.

## View and Run a S.M.A.R.T. Test

1. Open `Settings-Storage-HDD/SSD`.
2. Click the arrow to the right of `Health status` in the target drive row to open the `S.M.A.R.T. Test` dialog:
   ![S.M.A.R.T. test dialog](position://apps/settings/storage#smart-test-dialog)
3. The dialog states “Perform a S.M.A.R.T. test on the drive and report the result of the drive health status.”
4. View `Test result`. After the test runs to completion, the `Test result` field shows `Normal`; if you click [Stop] midway, the `Test result` field shows `Aborted`.
5. Click [Test] to start the test; during the test, the button changes to [Stop] and the test progress is shown. After clicking [Stop], the test result shows `Aborted`.
6. Click [Done] to close the dialog.

## View S.M.A.R.T. Details

1. Open `Settings-Storage-HDD/SSD`.
2. Click the arrow to the right of `Health status` for the target drive to enter the `S.M.A.R.T. Test` dialog.
3. Click the arrow to the right of `Test result` to open `Details`:
   ![S.M.A.R.T. details](position://apps/settings/storage#smart-detail-info)
4. In the details table, view the S.M.A.R.T. index status returned by the drive.
5. Click [Done] to close the details window.
<!-- legacy-faq-p0-p1 -->

## FAQ

| Question | Handling or suggestion |
| --- | --- |
| What file system does the internal storage pool use? | ZettOS internal storage pools use the Btrfs file system. Creating or rebuilding a storage pool formats the selected drives, so back up data first. |
| Why can't I see data from an old drive after inserting it into the NAS? | Drives that were not formatted by a Zettlab NAS cannot be read directly through the SATA drive bays. Adding them to a storage pool starts a formatting flow, so do not create a storage pool from a drive that still contains data you need to migrate. |
| How can I read a drive removed from another device? | For a non-RAID drive, connect it to the NAS through a SATA-to-USB enclosure or dock and read it from the external storage entry. Common readable formats include NTFS, FAT32, exFAT, EXT2, EXT3, EXT4, Btrfs, and XFS; actual availability still depends on drive health and file-system integrity. |
| Are hardware RAID cards supported? | No. Use the storage modes provided in `Settings - Storage - Storage Pool`, such as Basic, JBOD, RAID 0, RAID 1, RAID 5, RAID 6, or RAID 10. |
| Where will I see a RAID or drive abnormality? | Check storage pool status, drive health, and system prompts in `Settings - Storage` first. Some devices may also show alerts on the front LCD or through notifications. |
| What should I do if RAID repair fails? | Stop writing data, avoid repeatedly unplugging drives, and record the prompt, drive bay, drive model, and recent operations. Contact official support before rebuilding or formatting again. |
| Will creating a Storage Pool affect existing data on the drives? | Yes. Creating a Storage Pool formats the selected drives and clears the data on them. The format warning indicates that this operation cannot be undone. See [Manage storage pools and drives](apps/settings/storage). |
| Why are some RAID modes unavailable? | Available storage modes depend on the number of selected drives. `RAID 0` / `RAID 1` require at least 2 drives, `RAID 5` requires at least 3 drives, `RAID 6` and `RAID 10` require at least 4 drives, and `RAID 10` requires an even number of drives. See [Manage storage pools and drives](apps/settings/storage). |
| When can I expand a Storage Pool? | When unused drives exist in the system, a JBOD Storage Pool shows the [Expand Storage Pool] entry. RAID 0 Storage Pools do not support expansion. See [Manage storage pools and drives](apps/settings/storage). |
| Why does the SSD Cache dialog show “No SSD Cache Available”? | SSD Cache requires an SSD larger than 32GB. When no eligible SSD is available, the [Confirm] button is disabled. See [Manage storage pools and drives](apps/settings/storage). |