Repair a Storage Pool

Storage pool errors might occur due to various reasons, such as damaged system partitions or crashed hard drives. In some cases, you can follow the steps below to diagnose the error and fix the issue.

Failed System Partitions

When system partitions fail, you should see a message informing you that the system partitions cannot be accessed.

To repair system partitions:

1. Open Storage Manager.

2. Go to Overview and click the link marked Repair. The system should repair the system partitions.

Degraded Storage Pools

A storage pool becomes Degraded when a hard drive fails, but data loss has not occurred. This only happens with RAID types that provide data redundancy, such as SHR, RAID 1, RAID 5, RAID 6, and RAID 10.

A degraded storage pool can be fixed by replacing the failed hard drive with a healthy one and repairing the storage pool.

To repair a degraded storage pool:

1. Go to Storage Manager > Storage Pool to confirm the status has changed to Degraded.

2. If so, go to the HDD/SSD tab to see which hard drive has failed.

3. Remove the failed hard drive and replace it with a new one.

Note:

• If your DiskStation does not support hot-swapping, please remember to power it off before removing and installing any hard drives.
• Existing data on the replacement hard drive will be erased.
4. After the replacement hard drive has been installed, return to the Storage Pool tab.
5. Select the degraded storage pool.
6. Click Repair from the Action drop-down menu.

7. Select the replacement hard drive which you would like to add to the volume. Then follow the instructions of the wizard to finish.

Repair Storage Pools

To repair a degraded storage pool, you need to replace the failed disk with an available disk that matches the following criteria:

• For RAID 1, RAID 5 or RAID 6 storage pools, the degraded volume can be repaired by an available disk whose size is equal to or larger than the size of the smallest disk in the storage pool.
• For SHR-1 storage pools, the available disk must meet one of the following criteria: (1) Its size must be equal to or larger than the size of the failed disk; (2) With the largest disk in the storage pool excluded, its size must be equal to or larger than the size of the largest remaining disk.
  1. Example 1: SHR-1 is composed of 3TB, 2TB, 2TB, and 1TB disks. If the 3TB disk fails, it can be repaired by an available disk whose size is equal to or larger than 2TB.
  2. Example 2: SHR-1 is composed of 4TB, 4TB, 2TB, and 2TB disks. If the 4TB disk fails, it can be repaired by an available disk whose size is equal to or larger than 4TB.
  3. Example 3: SHR-1 is composed of 4TB, 4TB, 2TB, and 2TB disks. If the 2TB disk fails, it can be repaired by an available disk whose size is equal to or larger than 2TB.
• For SHR-2 storage pools, the available disk must meet one of the following criteria: (1) Its size must be equal to or larger than the size of the failed disk; (2) With the two largest disks in the storage pool excluded, its size must be equal to or larger than the largest remaining disk.

If you have configured disks as hot spares that match the above criteria, they will be used for repairing the storage pool.

Resolve Crashed Storage Pools

When the status of a volume becomes Crashed, you cannot repair the volume by yourself. To solve this problem, we recommend contacting our Technical Support for help.