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Which RAID levels require initialisation?
Parity‑based RAID levels (RAID 5, RAID 6, RAID 50, and RAID 60) require initialisation. RAID 0, RAID 1 and RAID 10 do not.
What’s the difference between foreground and background initialisation?
A foreground initialisation completes faster but requires the device to be disconnected from the host computer and unavailable during the process.
A background initialisation runs more slowly but allows continued access to the device while it completes.
Does initialisation delete my data?
Yes. Creating and initialising a RAID array deletes all files stored on the drives. Always back up important files before creating an array.
Initialisation has been running for days. Has initialisation become stuck?
Not necessarily. With large‑capacity drives and parity‑based RAID levels, initialisation can take many days and, in some cases, more than a week — especially when using background initialisation.
Can I stop or pause an initialisation once it starts?
RAID Manager does not provide a way to manually pause or stop an initialisation.
If a foreground initialisation is interrupted, it must be restarted from the beginning.
A background initialisation automatically resumes if the device is powered off or disconnected, but it cannot be intentionally paused or resumed by the user.
Can I disconnect my computer during initialisation?
Yes, depending on the type of operation.
During background initialisation, the operation continues if the computer is disconnected and resumes automatically when power is restored.
During foreground initialisation, disconnecting the device or losing power interrupts the operation and requires it to be restarted from the beginning.
When do I need to format the array?
Formatting is required when creating a new array, changing the RAID level, replacing all drives in an array, or preparing the device for use with a different operating system.
Does formatting erase all data on the array?
Yes. Formatting permanently deletes all data stored on the array.
Why does the array format show as “None”?
None indicates that the array is not currently formatted. In most cases, this means the array has been created but has not yet been formatted with a file system.
In rare cases, None may be displayed if RAID Manager cannot detect the array due to a hardware or software issue. Possible causes include a problem with the device’s internal electronics or with the RAID Manager driver.
To troubleshoot, power off the storage device, wait at least one minute, then power it back on and reconnect it to the host computer.
If the issue persists, shut down the host computer completely. After waiting about 30 seconds, restart the computer and reconnect the storage device.
Should I format the array using RAID Manager or my computer’s disk utility?
You can format the array using either RAID Manager or your operating system’s disk utility. RAID Manager uses the same underlying formatting mechanisms as the operating system.
By default, RAID Manager formats as APFS on macOS and NTFS on Windows. To format the array with another file system such as exFAT or HFS+, format the storage with a disk utility:
What does “Degraded” or “Partially Degraded” mean?
These states indicate reduced redundancy due to one or more drive failures. Data protection is limited until failed drives are replaced and the array is rebuilt.
What happens if a drive fails in my array?
If the selected RAID level provides redundancy, the array continues operating with reduced protection. Replacing the failed drive allows RAID Manager to rebuild the array and restore redundancy.
Note — If the failed drive is under warranty, you can check warranty status at www.seagate.com/warranty. Contact Seagate customer support at www.seagate.com/support for information about drive replacement.
What is a consistency check, and when should I run one?
A consistency check recalculates and verifies parity data to ensure data integrity and can automatically repair certain parity-related errors. It is useful as periodic maintenance but may reduce performance while running.
What is a spare drive?
A spare drive is reserved to automatically replace a failed drive in a redundant array. It is not available for normal storage while assigned as a spare.
Do I need a spare drive?
A spare drive is optional and recommended when minimising downtime is a priority. The spare remains inactive during normal operation and is used only if a drive fails. While a spare drive reduces the time an array operates in a degraded state, during normal operation it cannot be used for data storage or performance. If maximising usable capacity is more important, consider a redundant RAID level such as RAID 5, which allows all available drives to be used for storage instead of reserving one as a spare.
Note — If the failed drive is under warranty, you can check warranty status at www.seagate.com/warranty. Contact Seagate customer support at www.seagate.com/support for information about drive replacement.
What’s the difference between a dedicated spare and a global spare?
A dedicated spare is assigned to a specific array, while a global spare can be used by any compatible array on the device.
What happens to unconfigured drives?
Under normal operation for the arrays on the device, an unconfigured drive will remain unused. However, the RAID controller may assign an unconfigured drive as a spare to maintain the integrity of an array that has a failed drive. This will result in deleting all data on the unconfigured drive.
Why are some actions unavailable or disabled in RAID Manager?
Available actions depend on the current state of the array. Certain actions may be unavailable while another operation is in progress or when the array is degraded or offline.
Can I perform more than one operation at a time (for example, initialisation and a disk check)?
No. Operations such as initialisation, consistency checks, and RAID level changes must be performed sequentially.